• Option B is correct. Statements 1 and 3 are not correct.Statement 2 is correct.
Hydrogen is one of the most abundant elements on earth for a cleaner alternative fuel option.
Type of hydrogen depend up on the process of its formation:
Green hydrogen is produced by electrolysis of water using renewable energy (like Solar, Wind) and has a lower carbon footprint. Electricity splits water into hydrogen and oxygen. By Products are Water and Water Vapor.
Brown hydrogen is produced using coal where the emissions are released to the air.
Grey hydrogen is produced from natural gas where the associated emissions are released to the air.
Blue hydrogen is produced from natural gas, where the emissions are captured using carbon capture and storage.

• Option C is correct.
• Kaziranga National Park is a world heritage site and designated so in 1985.Kaziranga is located in the floodplains of the Brahmaputra River. It is one of the best wildlife sanctuaries in the world, home to world’s largest population of the Indian rhinoceros (pictured), as well as tiger, Asian elephant, wild water buffalo, and the Ganges river dolphin. The wetlands are important for migratory bird species.
• Keoladeo National Park is a world heritage site and designated so in 1985 .Initially a duck-hunting reserve for Maharajas, Keoladeo is a man-made and man-maintained wetland. It is important both for migratory and resident birds, especially waterbirds. Over 350 species of birds have been recorded, including 15 species of herons, Siberian crane, and greater spotted eagle.
• Sunderbans National Park are a World heritage site and was conferred such status in 1987.The national park covers the Indian part of the Sundarbans, the delta of the Ganges and Brahmaputra rivers. It is the world’s largest and richest mangrove forest, with about 78 recorded mangrove species. It is a biodiversity hotspot, home to a large population of Bengal tigers (one pictured), as well as an important habitat for the Irrawaddy dolphin and Ganges river dolphin, several species of birds and sea turtles.
• In addition to sites inscribed on the World Heritage List, member states can maintain a list of tentative sites that they may consider for nomination. Nominations for the World Heritage List are only accepted if the site was previously listed on the tentative list.As of 2022, India lists 52 properties on its tentative list.Neora valley National Park is one among them and not world heritage site currently.

• Option D is correct.
• Jerdon’s Courser is endemic to southern India, where it is principally known from southern Andhra Pradesh. It has an extremely limited geographical range being known from the Godavari river valley near Sironcha and Bhadrachalam, and from the Cuddapah and Anantapur areas in the valley of the Pennar River.It is listed as Critically Endangered in the IUCN Red List of Threatened Species.
• Sociable lapwing is a critically endangered species in the lapwing family of birds.It breeds on open grassland in Russia and Kazakhstan and migrates to north-west India during winters.
• Bugun Liocichla is one of the few new bird species to have been discovered in India since 1947 as well as in the last decade.They are found only in the Singchung village of Arunachal Pradesh. It has been named after the Bugun tribe.IUCN status is Critically Endangered (CR) for this bird species.
• Spoon billed Sandpiper is a rare species that inhabits grasslands and intertidal zones of the coastal region from the sea level up to 70m. It is migratory, breeding in north-eastern Russia and wintering in India, Bangladesh, Myanmar and Southeast Asian countries like Japan. It sometimes congregates in large numbers especially around the migratory season and gets dispersive in small groups on wintering grounds.This species is listed as Critically Endangered in the IUCN Red List of Threatened Species.

• Option B is correct.
Critically endangered is the highest risk category assigned by the IUCN (International Union for Conservation of Nature) Red List of wild species. There are five quantitative criteria to determine whether a taxon is threatened. A taxon is critically endangered when the best available evidence indicates that it meets any of the following criteria:
o Populations have declined or will decrease, by greater than 80% over the last 10 years or three generations.
o Have a restricted geographical range.
o Small population size of less than 250 individuals and continuing decline at 25% in 3 years or one generation.
o Very small or restricted population of fewer than 50 mature individuals.
o High probability of extinction in the wild.

• Option C is correct.
• Gross primary productivity refers to the amount of organic substance synthesized by the producers in unit time per unit area.Net Primary productivity refers to the amount of organic substance stored by autotrophs or producers in unit time per unit area. Hence,statement 1 is incorrect.
• Net primary productivity of Tropical rainforest is greater than Estuaries.Tropical rainforest are the most productive ecosystem next only to the Coral reefs. Hence, statement 2 is correct.
• Plants typically capture and convert about 1.3 -1.6% of the solar energy that reaches Earth’s surface and use about a quarter of the captured energy for metabolism and maintenance. So, around 1% of the solar energy reaching Earth’s surface (per unit area and time) ends up as net primary productivity.Hence,statement 3 is incorrect.

• Option A is correct. Adsorption,Coagulation and Reverse Osmosis are used to remove arsenic from drinking water.
• Arsenic is known to be highly toxic to all life forms. This element has been classified by the World Health Organization as a group 1 human carcinogenic substance.
• Adsorption has been reported as the most widely used technique for arsenic removal due to its several advantages including relatively high arsenic removal efficiencies, easy operation, and handling , cost-effectiveness, and no sludge production. Iron-based adsorption is an emerging technique for the treatment of arsenic-contaminated water. This can be explained by the fact that there exists a high affinity between inorganic arsenic species and iron. Iron can remove arsenic from water either by acting as a sorbent, co-precipitant or contaminant-immobilizing agent, or by behaving as a reductant.
• Coagulation and flocculation are among the most employed and documented techniques for arsenic removal from water. In coagulation, positively charged coagulants (e.g., aluminum sulphate (Al2(SO4)3), ferric chloride (FeCl3)) reduce the negative charge of colloids, thereby making the particles collide and get larger. Flocculation, on the other hand, involves the addition of an anionic flocculant that causes bridging or charge neutralization between the formed larger particles leading to the formation of flocs. During these processes, dissolved arsenic is transformed by the chemicals into an insoluble solid, which undergoes precipitation later.
In view of drinking water production, membrane filtration is a technique that can be used for the removal of arsenic and other contaminants from water. A driving force, such as pressure difference between the feed and the permeate sides, is needed to transport the water through the membrane. Generally, there are two categories of pressure-driven membrane filtrations: (i) low-pressure membrane processes, such as microfiltration (MF) and ultrafiltration (UF); and (ii) high-pressure membrane processes, such as reverse osmosis (RO) and nanofiltration (NF).
• Boiling of water does not remove Arsenic from water.

• Option B is correct.
• Sandalwood is a dry deciduous forest species native to China, India, Indonesia, Australia, and the Philippines. This small tropical tree grows to 20 m high with red wood and a variety of dark colors of bark (dark brown, reddish and dark grey). Because it is strong and durable, Sandalwood is mostly harvested for its timber. Sandalwood heartwood, which is close-grained, is used for fine furniture and carving.
• Five of the important trees found in tropical evergreen forests are rosewood, malabar kino, teak, Laurel and bamboo.In the fig family, the Laurel grows a fig-like fruit containing about 150 seeds. A single large tree will produce 100,000 fruits that are eaten and spread across the island by birds.
• Temperate deciduous forests have a great variety of plant species.Most have three levels of plants.Lichen, moss, ferns, wildflowers and other small plants can be found on the forest floor.Shrubs fill in the middle level and hardwood trees like maple, oak, birch, magnolia, sweet gum and beech make up the third level.Conifers like spruce, fir and pine trees can also be found mixed in with the hardwood trees in this biome.Sometimes the taiga and the temperate deciduous forest overlap.

• Option B is correct.
• Mercury is introduced into the environment in three ways. First, mercury is emitted into the air naturally from volcanoes, the weathering of rocks, forest fires, and soils. Second, mercury is emitted into the air from the burning of fossil fuels and municipal or medical waste. Lastly, mercury can be re-introduced into the environment through natural processes such as evaporation of ocean water. Hence,statement 1 is incorrect.
• When released into the environment, it accumulates in water-laid sediments where it converts into toxic methylmercury and enters the food chain. Mercury contamination is a significant public health and environmental problem because methylmercury easily enters the bloodstream and affects the brain.Mercury, such as thiomersal (ethylmercury), is used in very small amounts as a preservative in some vaccines and pharmaceuticals. Compared to methylmercury, ethylmercury is very different. Ethylmercury is broken down by the body quickly and does not accumulate. Hence,statement 2 is incorrect.
• Minamata disease was first discovered in Minamata city in Kumamoto prefecture, Japan in 1956 was caused by the release of methyl mercury in the industrial wastewater from the Chisso Corporation’s Chemical factory, which continued from 1932 to 1968. It is also referred to as Chisso-Minamata disease, is a neurological syndrome caused by severe mercury poisoning. Symptoms include ataxia, numbness in the hands and feet, general muscle weakness, narrowing of the field of vision and damage to hearing and speech. In extreme cases, insanity, paralysis, coma, and death follow within weeks of the onset of symptoms.Hence,statement 3 is correct.

• Option B is correct.
“Biodiversity Heritage Sites” (BHS) are well defined areas that are unique, ecologically fragile ecosystems – terrestrial, coastal and inland waters and, marine having rich biodiversity. Under Section 37 of Biological Diversity Act, 2002 (BDA) the State Government in consultation with local bodies may notify in the official gazette, areas of biodiversity importance as Biodiversity Heritage Sites (BHS). Hence, both statement 1 and statement 2 are not correct.
• Ameenpur Lake became the first water body in the country to be declared a Biodiversity Heritage Site. It is located on the western fringes of Hyderabad in Telangana state. It is a man-made lake and was constructed during the reign of Ibrahim Qutab Shah, who ruled the kingdom of Golconda between 1550 and 1580. Hence, statement 3 is correct.
• The Biodiversity Management Committee or other appropriate institution as determined by relevant local body in the absence of BMCs, which in addition to their duties defined in the Act, may also take care of the management of each BHS.

• Option D is correct. Statements 1 and 3 are incorrect. Only statement 2 is correct.
• At the 27th Session of Conference of Parties (COP27), this year’s UN climate summit, the Mangrove Alliance for Climate (MAC) was launched with India as a partner on Tuesday (November 8). The move, in line with India’s goal to increase its carbon sink, will see New Delhi collaborating with Sri Lanka, Indonesia and other countries to preserve and restore the mangrove forests in the region. Hence,statement 2 is correct.
• An initiative led by the United Arab Emirates (UAE) and Indonesia, the Mangrove Alliance for Climate (MAC) includes India, Sri Lanka, Australia, Japan, and Spain. It seeks to educate and spread awareness worldwide on the role of mangroves in curbing global warming and its potential as a solution for climate change.
The intergovernmental alliance works on a voluntary basis which means that there are no real checks and balances to hold members accountable. Instead, the parties will decide their own commitments and deadlines regarding planting and restoring mangroves. The members will also share expertise and support each other in researching, managing and protecting coastal areas. Hence, statements 1 and 3 are incorrect.