UPSC Civil Services (Preliminary) Exam 2023 Paper I (General Studies) 28 May 2023 (Answer Key)

• India is the world’s ninth-largest producer of uranium, with an output of 617 Tonnes in 2022, up by 0.26% in 2021. However, Coal is still the most important and abundant fossil fuel in India. It accounts for 55% of the country’s energy needs. So, statement 1 is correct.
• Uranium is an element which occurs naturally. It can have nuclear-related uses once it has been refined, or enriched. This is achieved by increasing the content of its most fissile isotopes, U-235, through the use of centrifuges – machines which spin at supersonic speeds.
• Low-enriched uranium, which typically has a 3-5% concentration of U-235, can be used to produce fuel for commercial nuclear power plants. So, statement 2 is not correct.
• Highly enriched uranium has a purity of 20% or more and is used in research reactors. Weapons-grade uranium is 90% enriched or more.

Therefore, option (c) is the correct answer.

• Marsupials (Metatheria) are pouched mammals, that is mammals in which the females bear their young alive but in an almost foetal state and, in most species, carry them within an external pocket or pouch formed by a flap of dermal tissue on the abdomen. The most familiar marsupials are the kangaroos. The Marsupials are native to Australia. They are not naturally found in India. So, statement 1 is correct.
• Marsupials are mostly found in arid and semi-arid regions and not only in montane grasslands with no predators. So, statement 2 is not correct.

Therefore, option (c) is the correct answer.

• The Global Invasive Species Database was developed and is managed by the Invasive Species Specialist Group’ of the Species Survival Commission of the International Union for Conservation of Nature. It was developed as part of the global initiative on invasive species led by the erstwhile Global Invasive Species Programme (GISP) in 2000. The GISD over the past two years and has been redesigned with support from the Abu Dhabi Environment Agency, the Italian Ministry of Environment and ISPRA – the Institute for Environmental Protection and Research, Italy.
  

Therefore, option (a) is the correct answer.

• Lion-tailed macaque, also known as the wanderoo, thrives in the upper canopy of tropical evergreen rainforests and monsoon forests, at a wide range of elevations, from 330 to 6,000 ft (100–1,850 m). They are endemic to the Western Ghats. Lion-tailed macaques are diurnal and live in groups of 10 to 20 individuals. So, point 1 is not correct.
• Malabar Civet is a nocturnal and elusive animal. It is endemic to Western Ghats of India. They are mainly found in Wooded plains and hill slopes of evergreen rainforests. So, point 2 is correct.
• Sambar deer is native to the Indian subcontinent and Southeast Asia that is listed as a vulnerable species on the IUCN Red List since 2008. Sambar are nocturnal or crepuscular animals and rest during the day under the cover of heavy forest. So, point 3 is correct.
  

Therefore, option (b) is the correct answer.

• Honeybees live in colonies with one queen running the whole hive. Worker honeybees are all females and are the only bees most people ever see flying around outside of the hive. They forage for food, build the honeycombs, and protect the hive.
• Honey bees use “waggle dance” to communicate the direction, distance, and quality of a resource to nestmates by encoding celestial cues, retinal optic flow, and relative food value into motion and sound within the nest.

Therefore, option (c) is the correct answer.

• Mushrooms act as antibacterial, immune system enhancer and cholesterol lowering agents; additionally, they are important sources of bioactive compounds. As a result of these properties, some mushroom extracts are used to promote human health and are found as dietary supplements. So, statement 1 is correct.
• Psychedelic mushrooms are wild or cultivated mushrooms that contain psilocybin, a naturally occurring psychoactive and hallucinogenic compound. So, statement 2 is correct.
• Recently, an increasing number of mushrooms have been found to contain insecticidal compounds. Among these are species ofLactarius (Russulaceae), which react to wounding by exuding a milky fluid and/or color change reactions, which could be a warning reaction. So, statement 3 is correct.
• A mushroom documentation project in the forests of Northeast India has revealed a bioluminescent or light emitting variety of mushroom. The new species — named Roridomyces phyllostachydis was first sighted on a wet August night near a stream in Meghalaya’s Mawlynnong in East Khasi Hills district and later at Krang Shuri in West Jaintia Hills district. It is now one among the 97 known species of bioluminescent fungi in the world. So, statement 4 is correct.
  

Therefore, option (d) is the correct answer.

• Indian squirrels are found in India (south of the Vindhyas) and Sri Lanka. They live in tropical dry forests, rainforests, mangrove forests, grasslands, scrub, parks, gardens, and urban areas. They are solitary and only come together during the breeding season. They are active during the day spending their time both in trees and on the ground. Sometimes they live in a system of burrows that they use for shelter and storage. So, statement 1 is correct.
• They store their food materials like nuts and seeds in the ground. Squirrels hide nuts this way as preparation for cold weather when otherwise food will be scarce. So, statement 2 is correct.
• Indian squirrels are omnivores. They feed mainly on nuts and fruits but will also eat seeds, insects, small mammals and reptiles, eggs, and even sometimes chicks of bird. So, statement 3 is correct.

Therefore, option (c) is the correct answer.

• “Thermophiles” are microorganisms with optimal growth temperatures between 60 and 108 degrees Celsius. They are isolated from a number of marine and terrestrial geothermally-heated habitats including shallow terrestrial hot springs, hydrothermal vent systems, sediment from volcanic islands, and deep-sea hydrothermal vents. The boiling point of water is 100 degrees Celsius. So, statement 1 is correct.
• The microorganisms live in every part of the biosphere, and some of them are even capable of growing at low temperatures, including those below the freezing point. These microorganisms live in the sea or in high mountains, but unfortunately also in refrigerators, where they may spoil or, as pathogens contaminate foods. So, statement 2 is correct.
• Microorganisms that grow optimally at pH less than 5.55 are called acidophiles. For example, the sulfuroxidizing Sulfolobus spp. isolated from sulfur mud fields and hot springs in Yellowstone National Park are extreme acidophiles. These archaea survive at pH values of 2.5–3.5. So, statement 3 is correct.
  

Therefore, option (c) is the correct answer.

• Orangutans are the largest arboreal mammal, spending most of their time in trees. Long, powerful arms and grasping hands and feet allow them to move through the branches. These great apes share 96.4% of our genes and are highly intelligent creatures.
• They have been observed as using sticks for fishing out bugs from bark. Researchers have also spotted orangutans using sticks to extract seeds from fruit and scrape insects from a hole in a tree in the wild.
• The name orangutan means “man of the forest” in the Malay language. In the lowland forests in which they reside, orangutans live solitary existences. They feast on wild fruits like lychees, mangosteens, and figs, and slurp water from holes in trees. They make nests in trees of vegetation to sleep at night and rest during the day.

Therefore, option (b) is the correct answer.

• Hydrofluorocarbons (HFCs) are a group of industrial chemicals primarily used for cooling and refrigeration. HFCs were developed to replace stratospheric ozone-depleting substances that are currently being phased out under the Montreal Protocol on Substances that Deplete the Ozone Layer.
• HFCs are entirely man-made. They are primarily produced for use in refrigeration, air-conditioning, insulating foams and aerosol propellants, with minor uses as solvents and for fire protection. HFCs are not used for making lubricants. So, Points 1, 2 and 3 are correct and point 4 is not correct.

Therefore, option (c) is the correct answer. 

• Wular Lake is the largest freshwater lake in India and is located in Jammu and Kashmir. It lies at the north end of the Vale of Kashmir, 20 miles (32 km) north-northwest of Srinagar. The lake controls the flow of the Jhelum River, which traverses it. So, statement 1 is correct.
• Kolleru Lake is fed directly by water from the seasonal Budameru and Tammileru streams and is connected to the Krishna and Godavari systems by over 68 inflowing drains and channels. It serves as a habitat for migratory birds. Thus, the Krishna River does not directly feed Kolleru Lake. So, statement 2 is not correct.
• Kanwar Lake, also known as Kabar Taal, is the largest freshwater lake in Bihar. Kanwar jheel, as it is locally called, is located 22 km north-west of Begusarai town. It is a residual oxbow lake, formed due to meandering of Gandak river, a tributary of Ganga, in the geological past. So, statement 3 is correct.

Therefore, option (b) is the correct answer.

• Kamarajar Port, located on the Coromandel Coast north of Chennai Port, Chennai, is the 12th major port of India, and the first port in India which is a public company. The port was declared as a major port under the Indian Ports Act, 1908 in March 1999 and incorporated as Ennore Port Limited under the Companies Act, 1956 in October 1999. So, Statement 1 is correct.
• Mundra Port is India’s first private port and largest privately owned port, located on the northern shores of the Gulf of Kutch near Mundra, Kutch district, Gujarat. So, Statement 2 is correct.
• Visakhapatnam Port is India’s third largest state-owned port by volume of cargo handled and the largest on the Eastern Coast. It is located midway between the Chennai and Kolkata Ports on the Bay of Bengal. Jawaharlal Nehru Port (Nhava Seva), Maharashtra, is the largest container port in India. So, Statement 3 is not correct.

Therefore, option (b) is the correct answer.

• Jackfruit (Artocarpus heterophyllus) is an evergreen tree, which means they retain their leaves throughout the year and do not shed them seasonally. So, Point 1 is not correct.
• Mahua (Madhuca indica) is found in the dry deciduous type of forests like the Forests of Chhattisgarh and Jharkhand. So, Point 2 is correct. 
• Teak (Tectona grandis) is a moist deciduous tree. Teak wood forests are mainly found in North East India. So, Point 3 is correct.

Therefore, option (b) is the correct answer.

• Arable land is land ploughed or tilled regularly. India has the most arable land in the world followed by the United States, Russia, China and Brazil.
• India and the United States account for roughly 22% of the world’s arable land.
• India has the largest arable land of any country at 1,656,780 km square (50.4% of total land) compared with 1,084,461 km square (11.3% of total land) of China. So, statement 1 is correct.
• India has more proportion of irrigated land than China. China’s irrigation cover is 41% of the cultivated area, and India’s is 48%. So, statement 2 is correct.
• However, the average productivity per hectare is higher in China i.e., 4.7 tonnes per hectare compared to India’s 2.7. So, statement 3 is not correct.

Therefore, option (b) is the correct answer.

• The Rann of Kutch is a vast salt marsh located in the Thar Desert of Gujarat, India. It is known for its unique ecosystem and is characterized by extensive marshy areas.
• The region has experienced multiple cycles of sea level fluctuations over time, leading to the formation of the marshland in the present day.
• The Rann was once a shallow part of the Arabian Sea until a geological shift closed off the connection with the sea. The region became a seasonal marshy salt desert over the years. During monsoons, the region fills up with water and forms a wetland. In the summer the water dries to create a bed of white salty land.

Therefore, option (d) is the correct answer.

• Ilmenite and rutile, which are abundantly available in certain coastal tracts of India, are rich sources of titanium. Titanium is a strong and lightweight metal widely used in various industries, including aerospace, automotive, and medical.
• India is endowed with large resources of heavy minerals which occur mainly along coastal stretches of the country and also in inland placers. Heavy mineral sands comprise a group of seven minerals, viz, ilmenite, leucoxene (brown ilmenite), rutile, zircon, sillimanite, garnet and monazite. Ilmenite (FeO.TiO₂) and rutile (TiO₂) are the two chief minerals of titanium

Therefore, option (d) is the correct answer. 

• About three-fourths of the world’s cobalt, a metal required for the manufacture of batteries for electric motor vehicles, is produced by the Democratic Republic of the Congo.
• The Democratic Republic of the Congo (DRC) is a major global producer of cobalt and has significant cobalt reserves, making it a critical player in the supply chain for electric vehicle batteries.

Therefore, option (c) is the correct answer.

• Cameroon is a part of the Congo Basin. The Congo Basin is a vast region in Central Africa that encompasses several countries, including Cameroon.
• Congo basin, basin of the Congo River, lying astride the Equator in west-central Africa. It is the world’s second-largest river basin (next to that of the Amazon), comprising an area of more than 1.3 million square miles (3.4 million square km). The vast drainage area of the Congo River includes almost the whole of the Republic of the Congo, the Democratic Republic of the Congo, the Central African Republic, western Zambia, northern Angola, and parts of Cameroon and Tanzania.
• Countries wholly or partially in the Congo region:
  • Angola
    
  • Gabon
  • Burundi
  • Cameroon
  • Central African Republic
  • Democratic Republic of the Congo
  • Republic of the Congo
  • Rwanda 
  • Tanzania
  • Zambia

Therefore, option (a) is the correct answer.

• Amarkantak is a pilgrimage town located in the Anuppur District of Madhya Pradesh, India. It is known for being the source of the Narmada River, Mahanadi and Son Rivers. It is located in South Eastern Madhya Pradesh. So, Statement 1 is not correct.
• The Biligirirangan Hills, do not constitute the easternmost part of the Satpura Range and are located in the Chamarajanagar district of Karnataka, India. They are part of the Eastern Ghats mountain range, not the Satpura Range. So, Statement 2 is not correct.
• The Seshachalam Hills, also known as the Tirumala Range are hill ranges of the Eastern Ghats, located in southern Andhra Pradesh. They are bounded by the Rayalaseema uplands in the west and northwest and the Nandyal Valley in the northeast. So, Statement 3 is not correct.

Therefore, option (d) is the correct answer.

• The Golden Quadrilateral Project is a major highway development project in India that aims to connect the four major metropolitan cities: Delhi, Mumbai, Chennai, and Kolkata. The East-West Corridor is a part of this project and connects Silchar in Assam to Porbandar in Gujarat. So, Statement 1 is not correct
• The IMT Trilateral Highway connects Moreh in the Indian state of Manipur with Mae Sot in Thailand, passing through Myanmar. It is an ambitious infrastructure project aimed at enhancing connectivity and trade between India, Myanmar, and Thailand. So, Statement 2 is not correct.
• The Bangladesh-China-India-Myanmar Economic Corridor (BCIM) Corridor is a proposed connectivity project that aims to enhance economic cooperation and trade between Bangladesh, China, India, and Myanmar. The corridor is expected to run from Kunming in China, through Myanmar, and Bangladesh, and eventually reach Kolkata in India. So, Statement 3 is not correct.

Therefore, option (d) is the correct answer.