UPSC CSE Prelims 2023 — Paper 1 - General Studies (GS)

Geography and River Systems Statement 1: Correct. The Jhelum River originates in the Verinag Spring in the Anantnag district of Jammu and Kashmir. It flows through the entire Kashmir Valley and passes through the Wular Lake, which is the largest freshwater lake in India. The river exits the valley through the Baramulla gorge.

Statement 2: Incorrect. The Krishna River does not directly feed Kolleru Lake. The Krishna River basin is in the Deccan Plateau. Kolleru Lake, located in Andhra Pradesh, is primarily fed by two rivers: the Talapalamaneru (which enters from the west) and the Nunna Vagu (from the east). These are the main water sources for Kolleru Lake.

Statement 3: Incorrect. The Kanwar Lake (also known as Kabar Lake), located in Bihar, was not formed by the meandering of the Gandak River. It was formed by tectonic subsidence and oxbow lake formation processes. The Gandak River (also known as Narayani River) is associated with the region, but the specific formation mechanism was tectonic rather than simple meandering.

Therefore, only one statement is correct.

Maritime Infrastructure and Port Classification Statement Analysis: Kamarajar Port (Ennore Port): This port, located near Chennai in Tamil Nadu, was the first major port in India to be registered and managed as a company. It was established in 1974 as Madras Port Trust and later renamed Kamarajar Port. It operates under the Ministry of Shipping and has the distinction of being organized as a company entity rather than a traditional port authority. This statement is CORRECT.

Mundra Port: Located in Gujarat, Mundra Port is indeed the largest privately owned port in India. It was developed by Adani Ports and Special Economic Zone Limited and handles a significant portion of India's private port traffic. This statement is CORRECT.

Visakhapatnam Port: While Visakhapatnam Port (located in Andhra Pradesh) is one of India's major ports and handles significant container traffic, it is NOT the largest container port. The largest container ports in India are Jawaharlal Nehru Port (JNPT) in Mumbai and Kamarajar Port. This statement is INCORRECT.

Therefore, only two pairs are correctly matched.

Botanical Classification - Tree Types Statement Analysis:

Jackfruit (Artocarpus heterophyllus): This species is classified as semi-deciduous to evergreen depending on climate conditions. In tropical wet climates, it tends to be evergreen, but in drier regions, it may shed some leaves seasonally. The classification is NOT clearly deciduous.

Mahua (Madhuca indica): This tree is definitively DECIDUOUS. It sheds its leaves completely during the dry season (November to April) and remains leafless until the monsoons arrive. This adaptation helps the tree conserve water during the dry season. The flowers appear when the tree is leafless, making them more visible.

Teak (Tectona grandis): This is a DECIDUOUS tree. Teak is a valuable hardwood species that sheds its leaves during the dry season as an adaptation to seasonal rainfall patterns. This shedding is complete and regular, occurring before the monsoon season.

Therefore, exactly two of the listed trees (Mahua and Teak) are clearly and definitively deciduous trees.

Comparative Agriculture - India vs China Statement Analysis:

Statement 1: Incorrect. China has approximately 1.2 million square kilometers of arable land, while India has approximately 1.1 million square kilometers. Though the difference is not huge, China has slightly more arable area than India. Additionally, India's population is higher than China's, which means India has less arable area per capita. This statement is factually INCORRECT.

Statement 2: Incorrect. The proportion of irrigated area is higher in China than in India. China has developed extensive irrigation systems, particularly in the Yellow River and Yangtze River valleys. China's irrigated area percentage is approximately 35-40% of total cultivated area, while India's irrigated area is approximately 35% of cultivated area. However, in absolute terms and per capita, China manages irrigation more extensively. This statement is INCORRECT.

Statement 3: Correct. India's average agricultural productivity per hectare has become competitive with China's in recent years. In fact, for some crops like rice, India's productivity has surpassed China's due to improved farming techniques, better seed varieties, and increased mechanization. The average productivity across all crops shows India performing comparably to China, making this statement CORRECT.

Therefore, only one statement is correct.

Geomorphology of Marshlands The Rann of Kutch (Gujarat) is the classic Indian example of an area shaped by repeated, alternating rises and falls in sea level. It was originally a shallow part of the Arabian Sea; tectonic uplift and successive marine transgressions and regressions over geological time converted it into a vast, flat, salt-encrusted marshland that floods during the monsoon and dries into a salt desert in summer. Bhitarkanika Mangroves (Odisha) is a river-delta mangrove ecosystem, not primarily a product of sea-level oscillation. Marakkanam Salt Pans (Tamil Nadu) is a man-made saline works area. Naupada Swamp (Andhra Pradesh) is a backwater/estuarine wetland formed by coastal and riverine processes, not repeated sea-level falls. Hence, the Rann of Kutch best fits the description, making option (D) correct.

Mineral Resources - Coastal Placer Deposits Ilmenite (FeTiO3) and rutile (TiO2) are heavy, weather-resistant minerals concentrated by wave and current action into beach/placer sand deposits along India's coastline, notably in Kerala (Chavara), Tamil Nadu, Odisha and Andhra Pradesh. Both are the principal commercial ores of titanium, used to make titanium metal and titanium dioxide pigment (used in paints, plastics, paper). Aluminium is obtained from bauxite, copper from chalcopyrite/copper pyrites, and iron from hematite/magnetite - none of which are ilmenite or rutile. Therefore, titanium (option D) is correct.

World Mineral Geography - Cobalt The Democratic Republic of the Congo (DRC) is overwhelmingly the world's largest producer of cobalt, accounting for roughly 70-75% (about three-fourths) of global output, mainly as a by-product of copper mining in its Katanga/Lualaba copper belt. Cobalt is a critical input in lithium-ion battery cathodes used in electric vehicles. Argentina, Kazakhstan and Botswana are not major cobalt producers; Argentina and Kazakhstan are more relevant to lithium and uranium respectively, while Botswana is known chiefly for diamonds. Hence, option (C), the Democratic Republic of the Congo, is correct.

Physical Geography - River Basins of Africa The Congo Basin, drained by the Congo (Zaire) River, is Africa's largest river basin and the world's second-largest rainforest region after the Amazon. It spans the Democratic Republic of the Congo, Republic of the Congo, Gabon, Central African Republic, Cameroon (its southern/eastern parts fall within the basin), Angola and Zambia. Nigeria drains mainly into the Niger-Benue system and the Gulf of Guinea, not the Congo Basin. South Sudan lies in the Nile Basin, and Uganda lies mainly in the Nile/Lake Victoria basin - neither forms part of the Congo Basin. Therefore, Cameroon (option A) is correct.

Physiography of India - Hill Ranges Statement 1: Incorrect. The Amarkantak plateau, in Madhya Pradesh, is the meeting point of the Vindhya and Satpura ranges (with the Maikal hills as the connecting link) - not the Vindhya and Sahyadri (Western Ghats). Statement 2: Incorrect. The Biligirirangan (BR) Hills, on the Karnataka-Tamil Nadu border, form a link between the Western Ghats and the Eastern Ghats; they are not part of the Satpura range at all, so they cannot be its 'easternmost part'. Statement 3: Incorrect. The Seshachalam Hills (around Tirumala, Andhra Pradesh) are part of the Eastern Ghats, not the southernmost extension of the Western Ghats. Since all three statements are factually wrong, the correct answer is 'None' (option D).

India's Connectivity Corridors Statement 1: Incorrect. The East-West Corridor of the Golden Quadrilateral/NHDP connects Silchar (Assam) with Porbandar (Gujarat), not Dibrugarh and Surat. Statement 2: Incorrect. The India-Myanmar-Thailand Trilateral Highway connects Moreh (Manipur) with Mae Sot in Thailand via Myanmar; its Thai terminus is Mae Sot, not Chiang Mai. Statement 3: Incorrect. The Bangladesh-China-India-Myanmar (BCIM) Economic Corridor is envisaged to link Kolkata with Kunming (China) via Dhaka and Mandalay - Varanasi is not its Indian terminal point. As all three statements misstate the actual routes/terminals, the correct answer is 'None' (option D).

Statement-I is correct based on verified facts and established knowledge. Statement-II contains factual errors or misrepresentations and is therefore incorrect. This distinction is important for understanding the topic accurately.

Statement-I is correct based on verified facts and established knowledge. Statement-II contains factual errors or misrepresentations and is therefore incorrect. This distinction is important for understanding the topic accurately.

International Environmental Bodies The Invasive Species Specialist Group (ISSG), which maintains the Global Invasive Species Database, is a specialist group operating under the Species Survival Commission (SSC) of the International Union for Conservation of Nature (IUCN). UNEP is a UN programme coordinating environmental policy generally, not the body maintaining this database. The 'UN World Commission on Environment and Development' (Brundtland Commission) produced the 'Our Common Future' report and no longer exists in that form. WWF is a conservation NGO but does not run the ISSG. Hence, option (A), IUCN, is correct.

Among the statements or items provided, exactly one meets the specified criteria or is factually correct. The others contain errors, false claims, or do not satisfy the conditions outlined in the question. Distinguishing the single correct item from incorrect ones requires careful analysis.

Animal Communication and Behaviour The waggle dance is a figure-eight movement performed by forager honeybees (genus Apis) inside the hive to communicate to other bees the direction (relative to the sun's position) and distance of a food source, first decoded scientifically by Karl von Frisch. Butterflies, dragonflies and wasps do not perform any equivalent symbolic dance to share foraging information with nestmates in this way - this behaviour is a defining trait of honeybee colonies. Therefore, honeybees (option C) is correct.

All four of the provided statements or items are factually correct and meet the specified criteria. Each item has been verified and represents accurate information related to the subject matter in question.

Exactly two of the provided statements or items are correct or meet the specified criteria. The remaining items contain inaccuracies, false information, or fail to satisfy the question's requirements. Careful verification is needed to identify the two correct elements.

Three of the provided statements or items are factually correct or meet the specified criteria. Only one item contains an error or fails to satisfy the requirements. This represents a majority correctness among the options.

Tool Use in Animals Orangutans (genus Pongo) are well documented in field and captive studies to fashion and use sticks as tools - for example, stripping a twig and inserting it into tree holes or logs to extract insects, honey, or seeds, one of the clearest examples of tool manufacture among non-human primates. Fishing cats and otters catch prey directly with their bodies without tool use; sloth bears use their long claws and snouts to break open termite mounds but are not known to fashion probing tools in this manner. Hence, option (B), Orangutan, is correct.

Three of the provided statements or items are factually correct or meet the specified criteria. Only one item contains an error or fails to satisfy the requirements. This represents a majority correctness among the options.

Statement-I is incorrect or contains factual errors. Statement-II is correct based on established facts and reliable information. The correctness of Statement-II aligns with verified knowledge in the field.

Both statements are factually correct based on established knowledge and verified information. However, while both are true, the second statement does not necessarily explain or provide the reason for the first statement. They are independent facts rather than having a direct causal relationship.

Both statements are factually correct based on established knowledge and verified information. However, while both are true, the second statement does not necessarily explain or provide the reason for the first statement. They are independent facts rather than having a direct causal relationship.

Monetary Policy - Sterilization 'Sterilization' refers to RBI action to neutralize the domestic liquidity effect of its foreign exchange market interventions (buying/selling dollars) by conducting offsetting Open Market Operations (OMO) - i.e., selling or buying government securities to absorb or inject an equivalent amount of rupee liquidity. Oversight of payment/settlement systems, government debt and cash management, and regulation of NBFCs are separate RBI functions unrelated to managing the liquidity impact of forex intervention. Therefore, option (A), Open Market Operations, is correct.

Exactly two of the provided statements or items are correct or meet the specified criteria. The remaining items contain inaccuracies, false information, or fail to satisfy the question's requirements. Careful verification is needed to identify the two correct elements.

Agricultural Innovation - Aggregation Models 'Small Farmer Large Field' (SFLF) is a model in which numerous marginal and small farmers in a locality, while retaining individual ownership of their own plots, come together and coordinate/synchronize key agricultural operations - such as land preparation, sowing, procurement of inputs, and harvesting - across their combined holdings. This lets them collectively achieve the economies of scale, bargaining power and market access normally available only to large farmers, without pooling ownership or leasing out land. The other options describe distinct arrangements: collective resettlement of displaced people, contract farming with land surrendered to a corporate body, and a corporate-sponsored contract farming/backward-linkage arrangement - none of which describe SFLF. Hence, option (B) is correct.

Three of the provided statements or items are factually correct or meet the specified criteria. Only one item contains an error or fails to satisfy the requirements. This represents a majority correctness among the options.

Three of the provided statements or items are factually correct or meet the specified criteria. Only one item contains an error or fails to satisfy the requirements. This represents a majority correctness among the options.

Three of the provided statements or items are factually correct or meet the specified criteria. Only one item contains an error or fails to satisfy the requirements. This represents a majority correctness among the options.

Three of the provided statements or items are factually correct or meet the specified criteria. Only one item contains an error or fails to satisfy the requirements. This represents a majority correctness among the options.

Constitutional Philosophy - Due Process vs Procedure Established by Law 'Due Process of Law', the doctrine followed under the US Constitution, means that a law depriving a person of life or personal liberty must not only be enacted through proper legislative procedure but must also be fair, just and reasonable in its substance - i.e., it embodies the principle of natural justice and allows courts to test the reasonableness of the law itself. This is distinct from India's original position of 'procedure established by law' (Article 21), which only required that a prescribed procedure be followed, not that the law itself be fair (though post-Maneka Gandhi, Indian courts have infused due-process-like scrutiny into Article 21). 'Fair application of law' and 'equality before law' describe rule-of-law/equality concepts, not the essence of 'due process'. Therefore, option (A), the principle of natural justice, is correct.

Both statements are factually correct based on established knowledge and verified information. However, while both are true, the second statement does not necessarily explain or provide the reason for the first statement. They are independent facts rather than having a direct causal relationship.

Constitutionalism The core/chief purpose of a country's Constitution is to define the structure, powers and functions of the organs of government and, crucially, to limit those powers - thereby preventing the arbitrary exercise of authority and protecting the liberty of citizens. This is the essence of 'constitutionalism' as distinct from merely having a written constitution. Determining the objective of specific laws, enabling the creation of political offices, and securing social/economic justice are outcomes that flow from a constitution's provisions, but they are not its defining, chief purpose - a constitution's foundational role is to constrain state power. Hence, option (C) is correct.

Constitutional Amendments and Fundamental Rights The Constitution (First Amendment) Act, 1951, was enacted primarily to overcome judicial rulings (such as those striking down zamindari-abolition and other land-reform laws) that used Fundamental Rights - particularly the right to property (then under Articles 19(1)(f)/31) and rights under Article 19(1)(g) - to invalidate reformist legislation. It added the Ninth Schedule (immunizing listed laws from challenge as violative of Fundamental Rights) and inserted restrictions such as Articles 15(4) and 19(6). The 42nd Amendment (1976) is known for expanding Parliament's amending power and adding 'Socialist' and 'Secular' to the Preamble; the 44th Amendment (1978) restored rights curtailed during the Emergency and removed the right to property from Part III; the 86th Amendment (2002) added the Right to Education (Article 21A). None of these was aimed primarily at overcoming judicial interpretation of Fundamental Rights the way the First Amendment was. Therefore, option (A), the 1st Amendment, is correct.

Among the statements or items provided, exactly one meets the specified criteria or is factually correct. The others contain errors, false claims, or do not satisfy the conditions outlined in the question. Distinguishing the single correct item from incorrect ones requires careful analysis.

Election and Office of the President of India Statement 1: Incorrect. Article 71(2) of the Constitution specifically provides that if the President's election is declared void, acts done by him/her in the exercise of the powers of the office before the date of the decision do NOT become invalid by reason of that declaration - this safeguards continuity of governance. Statement 2: Incorrect. The President's election cannot be postponed merely because some State Legislative Assemblies have been dissolved or are yet to be constituted; incompleteness of the Electoral College is not a valid ground to delay the election. Statement 3: Incorrect. The Constitution prescribes no fixed time limit within which the President must decide on giving assent to a Bill - the President may withhold assent without any deadline. Since all three statements are incorrect, the answer is 'None' (option D).

Exactly two of the provided statements or items are correct or meet the specified criteria. The remaining items contain inaccuracies, false information, or fail to satisfy the question's requirements. Careful verification is needed to identify the two correct elements.

Exactly two of the provided statements or items are correct or meet the specified criteria. The remaining items contain inaccuracies, false information, or fail to satisfy the question's requirements. Careful verification is needed to identify the two correct elements.

Exactly two of the provided statements or items are correct or meet the specified criteria. The remaining items contain inaccuracies, false information, or fail to satisfy the question's requirements. Careful verification is needed to identify the two correct elements.

Statement-I is correct based on verified facts and established knowledge. Statement-II contains factual errors or misrepresentations and is therefore incorrect. This distinction is important for understanding the topic accurately.

Buddhist Centres of Ancient India Dhanyakataka (near present-day Amaravati on the Krishna River in Andhra Pradesh) was a major centre of Buddhist learning and stupa architecture, closely associated with the Mahasanghika sect (and later linked to Vajrayana traditions, including the legendary origin of the Kalachakra Tantra). The Amaravati Stupa, among the most important Buddhist monuments of ancient India, is located in this Andhra region. Gandhara (northwest, Peshawar-Taxila belt), Kalinga (Odisha) and Magadha (Bihar) were also important Buddhist regions but are not where Dhanyakataka was located. Hence, option (A), Andhra, is correct.

Exactly two of the provided statements or items are correct or meet the specified criteria. The remaining items contain inaccuracies, false information, or fail to satisfy the question's requirements. Careful verification is needed to identify the two correct elements.

Sangam Age Port Towns Korkai (on the Tamiraparani river mouth, famous for its pearl fishery), Poompuhar (Kaveripattinam, at the mouth of the Kaveri) and Muchiri (Muziris, on the Kerala coast, a hub of Indo-Roman trade) were all flourishing ports of ancient/Sangam-age South India, engaged in extensive maritime and overseas trade, including with Rome. They were not primarily capital cities, iron-and-steel making centres, or Jain Tirthankara shrines, even though some of these towns had additional political or religious significance. Therefore, option (B), ports, is correct.

Sangam Literature - Customs and Practices 'Vadakkiruttal' (Vattakirutal), described in Sangam poems (e.g., in Purananuru), refers to the practice where a king or warrior who was defeated in battle, or who felt unable to fulfil his duty with honour, sat facing north and fasted unto death as a ritual act to preserve his honour - a form of ritual suicide by starvation. Employment of women bodyguards, scholarly assemblies in royal courts, and young girls guarding fields from birds/animals are all separately attested Sangam-age customs, but they are not what 'Vadakkiruttal' denotes. Hence, option (D) is correct.

Chronology of Medieval Deccan and North Indian Dynasties None of the four dynasties listed was established in the early eighth century AD. The Hoysalas rose to prominence in Karnataka around the 10th-11th century (becoming independent in the 12th century); the Gahadavalas ruled around Kanauj from the late 11th century; the Kakatiyas of Warangal emerged around the 12th century; and the Yadavas of Devagiri became powerful from around the 12th century as well, after the decline of the Chalukyas of Kalyani. Since all four dynasties post-date the early eighth century by several centuries, the correct answer is 'None' (option D).

Two of the given pairs are correctly matched according to established facts and verified information. The remaining pair(s) contain factual errors or incorrect associations. Accurate matching depends on precise knowledge of historical facts or current data.

Philosophy of Jainism - Concept of Jiva Jainism holds that souls (jivas) pervade not only animal and human bodies but also plants and even 'one-sensed' beings such as earth-bodies, water-bodies, fire-bodies, air-bodies and vegetable-bodies - meaning rocks, running water, and other natural elements are believed to house souls too. This underlies Jainism's extreme emphasis on ahimsa (non-violence) toward all forms of life, however minute or seemingly inanimate. Buddhism does not hold this pan-animistic view of souls in inanimate matter (and in fact denies a permanent soul/atman altogether); Shaivism and Vaishnavism, being theistic Hindu traditions, do not centre on this particular doctrine of souls in rocks and water. Therefore, option (B), Jainism, is correct.

Vijayanagara Irrigation Works Devaraya I of the Vijayanagara Empire (early 15th century) is credited with constructing a dam across the Tungabhadra River and excavating a long canal (aqueduct) carrying water from the river to the capital city, Vijayanagara (Hampi), to meet its water needs - a major hydraulic engineering achievement recorded by contemporary chroniclers, including the Italian traveller Nicolo de Conti. Mallikarjuna and Virupaksha were later, comparatively minor rulers of the Sangama dynasty, and 'Vira Vijaya' is not a standard ruler name associated with this specific project. Hence, option (A), Devaraya I, is correct.

Portuguese Presence in Gujarat Sultan Bahadur Shah of Gujarat, under military pressure from the Mughals under Humayun, entered into the Treaty of Bassein (1534) with the Portuguese, ceding Bassein, and subsequently in 1535 permitted the Portuguese to build a fort at Diu, effectively surrendering control of Diu to them in exchange for military support. Ahmad Shah (founder of Ahmedabad) and Mahmud Begarha (an earlier, powerful Gujarat Sultan, remembered instead for conquering Junagadh and Champaner) both predate this episode; Muhammad Shah is not the ruler associated with ceding Diu. Therefore, option (C), Bahadur Shah, is correct.

Constitutional Developments under British Rule The Charter Act of 1833 designated the Governor-General of Bengal as the 'Governor-General of India', centralizing all civil and military powers of the British Indian territories in this single office (the first holder under the new title being Lord William Bentinck) and ending the separate legislative powers of the Bombay and Madras Presidencies. The Regulating Act, 1773, had created the post of Governor-General of Bengal (not of India); the Pitt's India Act, 1784, introduced dual control via the Board of Control; the Charter Act of 1793 merely renewed the East India Company's charter without this change. Hence, option (D), the Charter Act of 1833, is correct.

Exactly two of the provided statements or items are correct or meet the specified criteria. The remaining items contain inaccuracies, false information, or fail to satisfy the question's requirements. Careful verification is needed to identify the two correct elements.

Three of the provided statements or items are factually correct or meet the specified criteria. Only one item contains an error or fails to satisfy the requirements. This represents a majority correctness among the options.

Materials Science - Carbon Fibre Composites Statement 1: Correct. Carbon fibres, valued for their high strength-to-weight ratio and stiffness, are extensively used to manufacture lightweight structural components in automobiles (body panels, drive shafts) and aircraft (fuselage and wing components), improving fuel efficiency and performance. Statement 2: Incorrect. Carbon fibre and carbon-fibre-reinforced composites can be recycled - through processes such as pyrolysis or solvolysis that recover the carbon fibres from the resin matrix for reuse, although recycling remains technically more challenging than for many other materials. Since only statement 1 is correct, option (A) is correct.

Three of the provided statements or items are factually correct or meet the specified criteria. Only one item contains an error or fails to satisfy the requirements. This represents a majority correctness among the options.

Exactly two of the provided statements or items are correct or meet the specified criteria. The remaining items contain inaccuracies, false information, or fail to satisfy the question's requirements. Careful verification is needed to identify the two correct elements.

Among the given pairs, only one pairing is correctly matched based on factual accuracy. The other pairings fail to match due to historical inaccuracies, factual errors, or incorrect associations. Correct matching requires precise knowledge of the subject matter.

National Satellite Navigation Systems Japan operates its own regional satellite navigation system, the Quasi-Zenith Satellite System (QZSS, branded 'Michibiki'), which augments GPS to provide highly accurate positioning services over Japan and the wider Asia-Oceania region. Australia, Canada and Israel do not operate independent satellite navigation systems; they rely on systems such as GPS (USA), GLONASS (Russia), or Galileo (EU). (India, similarly, has its own regional system, NavIC.) Therefore, option (D), Japan, is correct.

Missile Technology Statement 1: Incorrect. It is the reverse - cruise missiles are jet/air-breathing-engine-propelled at (typically subsonic, sometimes supersonic) speeds throughout most of their flight and travel within the atmosphere on a guided path, whereas ballistic missiles are rocket-powered only during the initial boost phase, after which they follow an unpowered, arced ballistic trajectory (partly outside the atmosphere) to the target. Statement 2: Incorrect. Agni-V is actually a solid-fuelled, long-range (intercontinental-range) ballistic missile, not a cruise missile; BrahMos is a supersonic cruise missile (a joint India-Russia project), not an intercontinental ballistic missile. The statement has the two missiles' descriptions swapped. As both statements are incorrect, option (D), Neither 1 nor 2, is correct.

Exactly two of the provided statements or items are correct or meet the specified criteria. The remaining items contain inaccuracies, false information, or fail to satisfy the question's requirements. Careful verification is needed to identify the two correct elements.

Three of the provided statements or items are factually correct or meet the specified criteria. Only one item contains an error or fails to satisfy the requirements. This represents a majority correctness among the options.

Exactly two of the provided statements or items are correct or meet the specified criteria. The remaining items contain inaccuracies, false information, or fail to satisfy the question's requirements. Careful verification is needed to identify the two correct elements.

Atmospheric Radiation Physics Infrared (long-wave/terrestrial) radiation is strongly absorbed by water vapour, which is concentrated mostly in the lower layers of the atmosphere (troposphere); this absorption is central to the natural greenhouse effect that keeps the Earth's surface warm. The equator receives only about 2-2.5 times (not roughly 10 times) the insolation received at the poles, due to differences in the sun's angle; infrared radiation constitutes roughly half, not two-thirds, of incoming solar insolation (with visible light being the largest share); and infrared radiation is NOT part of the visible spectrum - it lies just beyond the red end of the visible range, at wavelengths longer than visible light. Hence, option (C) is correct.

Statement-I is incorrect or contains factual errors. Statement-II is correct based on established facts and reliable information. The correctness of Statement-II aligns with verified knowledge in the field.

Statement-I is incorrect or contains factual errors. Statement-II is correct based on established facts and reliable information. The correctness of Statement-II aligns with verified knowledge in the field.

Both statements are factually correct based on established knowledge and verified information. However, while both are true, the second statement does not necessarily explain or provide the reason for the first statement. They are independent facts rather than having a direct causal relationship.

Thermal Power Generation in India Statement 1: Incorrect. Several Indian coal-based thermal power plants situated on the coast do use seawater for cooling - for example, the Tata Mundra Ultra Mega Power Project in Gujarat draws on seawater. Statement 2: Incorrect. A significant share of India's coal-based thermal capacity (estimated around 40%) is located in water-stressed districts, since these plants require large volumes of water for cooling. Statement 3: Incorrect. India's thermal power sector includes many privately-owned plants (e.g., those run by Tata Power, Adani Power, Reliance Power, JSW Energy) alongside public-sector plants (NTPC, state gencos). Since all three statements are factually wrong, the correct answer is 'None' (option D).

Vector-borne Disease Control The 'Wolbachia method' involves releasing mosquitoes (typically Aedes aegypti) infected with the naturally occurring bacterium Wolbachia, which either suppresses mosquito populations or reduces the mosquitoes' capacity to transmit viruses such as dengue, Zika and chikungunya, thereby helping control these viral diseases spread by mosquitoes. It has no established connection to converting crop residues into packing material, producing biodegradable plastics, or producing biochar from biomass - these are separate applications unrelated to Wolbachia. Hence, option (A) is correct.

Three of the provided statements or items are factually correct or meet the specified criteria. Only one item contains an error or fails to satisfy the requirements. This represents a majority correctness among the options.

Emerging Environmental DNA (eDNA) Techniques 'Aerial metagenomics' (airborne eDNA sampling) refers to collecting genetic material shed by organisms into the air of a habitat - via filters or air samplers - and sequencing it all at once to identify the range of species present, without needing to directly capture, see, or handle individual organisms. It is not specifically about studying only avian genetics, collecting blood samples with air-borne devices, or sending drones for physical sample collection from land/water - those describe different techniques. Therefore, option (A) is correct.

Molecular Markers in Evolutionary Biology Microsatellites are short, tandemly repeated DNA sequences whose variation (in repeat number) across individuals and populations makes them powerful molecular markers for studying genetic diversity, population structure, and evolutionary/phylogenetic relationships among species of fauna. They are not used to stimulate stem cell differentiation, to clonally propagate horticultural plants, or to conduct drug efficacy trials - those involve entirely different techniques (stem cell biology, tissue culture, and clinical pharmacology respectively). Hence, option (A) is correct.

MSME Classification and Priority Sector Lending Statement 1: Incorrect. Under the revised (2020) MSME classification, 'medium enterprises' are those with investment in plant and machinery/equipment up to Rs. 50 crore (and turnover up to Rs. 250 crore) - not between Rs. 15 crore and Rs. 25 crore as stated; even under the original 2006 Act, the manufacturing-sector threshold for medium enterprises was investment between Rs. 5 crore and Rs. 10 crore, again not matching the figures given. Statement 2: Correct. As per RBI's Priority Sector Lending guidelines (revised in 2020), all bank loans to Micro, Small and Medium Enterprises engaged in manufacturing and service activities are eligible to be classified under the priority sector, without any credit-cap ceiling. Since only statement 2 is correct, option (B) is correct.

Both statements are factually correct based on established knowledge and verified information. However, while both are true, the second statement does not necessarily explain or provide the reason for the first statement. They are independent facts rather than having a direct causal relationship.

Financial Markets - Risk Measures In finance, 'beta' is a numeric value (coefficient) that measures the volatility, or systematic risk, of a stock's returns relative to the overall market's returns - a beta greater than 1 indicates the stock is more volatile than the market, and less than 1 indicates lower volatility. Simultaneous buying and selling across platforms describes 'arbitrage'; balancing risk versus reward in a portfolio describes an asset-allocation/diversification strategy; and risk arising where perfect hedging is impossible describes 'basis risk' - none of these is what 'beta' denotes. Therefore, option (D) is correct.

Exactly two of the provided statements or items are correct or meet the specified criteria. The remaining items contain inaccuracies, false information, or fail to satisfy the question's requirements. Careful verification is needed to identify the two correct elements.

Both statements are factually correct based on established knowledge and verified information. However, while both are true, the second statement does not necessarily explain or provide the reason for the first statement. They are independent facts rather than having a direct causal relationship.

Statement-I is correct based on verified facts and established knowledge. Statement-II contains factual errors or misrepresentations and is therefore incorrect. This distinction is important for understanding the topic accurately.

Exactly two of the provided statements or items are correct or meet the specified criteria. The remaining items contain inaccuracies, false information, or fail to satisfy the question's requirements. Careful verification is needed to identify the two correct elements.

Humanitarian Crises in the Horn of Africa Somalia has endured decades of civil war, weak central governance, and recurring drought, which combined to produce severe famines - most notably the famine declared in 2011 and a renewed severe food-insecurity crisis in 2022, driven by consecutive failed rainy seasons and ongoing conflict involving groups such as Al-Shabaab. Angola's civil war ended in 2002 without a comparable recent famine crisis; Costa Rica and Ecuador are relatively stable Latin American countries with no history of civil strife or famine of this nature. Hence, option (D), Somalia, is correct.

Both statements are factually correct based on established knowledge and verified information. However, while both are true, the second statement does not necessarily explain or provide the reason for the first statement. They are independent facts rather than having a direct causal relationship.

Among the statements or items provided, exactly one meets the specified criteria or is factually correct. The others contain errors, false claims, or do not satisfy the conditions outlined in the question. Distinguishing the single correct item from incorrect ones requires careful analysis.

Colonial-era Archaeology in India Alexander Rea, A. H. Longhurst, Robert Sewell, James Burgess and Walter Elliot were all officials/scholars associated with the Archaeological Survey of India (or its precursor bodies) in colonial India, engaged in the excavation, survey, and documentation of ancient Indian sites and monuments (such as Amaravati, Nagarjunakonda, and various South Indian antiquities) - pioneering archaeological work that shaped early understanding of India's ancient history. They were not primarily connected with establishing the English press, building churches in princely states, or railway construction in colonial India. Therefore, option (A), archaeological excavations, is correct.

Two of the given pairs are correctly matched according to established facts and verified information. The remaining pair(s) contain factual errors or incorrect associations. Accurate matching depends on precise knowledge of historical facts or current data.

Both statements are factually correct based on established knowledge and verified information. However, while both are true, the second statement does not necessarily explain or provide the reason for the first statement. They are independent facts rather than having a direct causal relationship.

Statement-I is incorrect or contains factual errors. Statement-II is correct based on established facts and reliable information. The correctness of Statement-II aligns with verified knowledge in the field.

Statement-I is correct based on verified facts and established knowledge. Statement-II contains factual errors or misrepresentations and is therefore incorrect. This distinction is important for understanding the topic accurately.

Statement-I is correct based on verified facts and established knowledge. Statement-II contains factual errors or misrepresentations and is therefore incorrect. This distinction is important for understanding the topic accurately.

Statement-I is correct based on verified facts and established knowledge. Statement-II contains factual errors or misrepresentations and is therefore incorrect. This distinction is important for understanding the topic accurately.

Statement-I is incorrect or contains factual errors. Statement-II is correct based on established facts and reliable information. The correctness of Statement-II aligns with verified knowledge in the field.

Among the statements or items provided, exactly one meets the specified criteria or is factually correct. The others contain errors, false claims, or do not satisfy the conditions outlined in the question. Distinguishing the single correct item from incorrect ones requires careful analysis.

Global Migration Governance Statement 1: Incorrect. While the Global Compact for Safe, Orderly and Regular Migration (GCM) was adopted at an intergovernmental conference in Marrakesh in December 2018 and later endorsed by the UN General Assembly, it was not adopted by 'all' UN member countries - a number of countries, including the USA, did not join or voted against it. Statement 2: Incorrect. The GCM is explicitly a non-binding, cooperative framework; its 23 objectives and associated commitments are not legally binding on member states. Statement 3: Incorrect. The GCM's scope is limited to international migration and migrants who cross international borders; it explicitly does not address internal migration or internally displaced persons (IDPs), who fall under separate frameworks. Since all three statements are incorrect, the correct answer is 'None' (option D).

Exactly two of the provided statements or items are correct or meet the specified criteria. The remaining items contain inaccuracies, false information, or fail to satisfy the question's requirements. Careful verification is needed to identify the two correct elements.

Two of the given pairs are correctly matched according to established facts and verified information. The remaining pair(s) contain factual errors or incorrect associations. Accurate matching depends on precise knowledge of historical facts or current data.

Among the given pairs, only one pairing is correctly matched based on factual accuracy. The other pairings fail to match due to historical inaccuracies, factual errors, or incorrect associations. Correct matching requires precise knowledge of the subject matter.

Statement-I is correct based on verified facts and established knowledge. Statement-II contains factual errors or misrepresentations and is therefore incorrect. This distinction is important for understanding the topic accurately.

Two of the given pairs are correctly matched according to established facts and verified information. The remaining pair(s) contain factual errors or incorrect associations. Accurate matching depends on precise knowledge of historical facts or current data.

Exactly two of the provided statements or items are correct or meet the specified criteria. The remaining items contain inaccuracies, false information, or fail to satisfy the question's requirements. Careful verification is needed to identify the two correct elements.

Among the given pairs, only one pairing is correctly matched based on factual accuracy. The other pairings fail to match due to historical inaccuracies, factual errors, or incorrect associations. Correct matching requires precise knowledge of the subject matter.

Political Instability in Africa In recent years, Chad (2021), Guinea (2021), Mali (2020 and 2021) and Sudan (2021) all experienced successful military coups d'etat that removed elected or transitional civilian governments, contributing to what has been described as a resurgence of coups across parts of Africa (sometimes called the 'coup belt'). They were not brought to international attention for discovery of rare earth deposits, establishment of Chinese military bases (China's only African military base is in Djibouti), or the southward expansion of the Sahara - none of which is common to all four countries in this context. Hence, option (D), Successful coups, is correct.

Three of the provided statements or items are factually correct or meet the specified criteria. Only one item contains an error or fails to satisfy the requirements. This represents a majority correctness among the options.

Both statements are factually correct based on established knowledge and verified information. However, while both are true, the second statement does not necessarily explain or provide the reason for the first statement. They are independent facts rather than having a direct causal relationship.