Which of the following Sustainable Development Goals ensures availability and sustainable management of water and sanitation for all?

The correct answer is B, 2005. The Kyoto Protocol came into force on 16 February 2005. It had been adopted at Kyoto in Japan on 11 December 1997 as the first binding agreement under the United Nations Framework Convention on Climate Change of 1992. It could start only after 55 parties had ratified it, including developed countries that accounted for at least 55 per cent of the 1990 carbon dioxide emissions of that group. Russia’s ratification in November 2004 crossed that mark, and the treaty began ninety days later. Its first commitment period ran from 2008 to 2012 and asked developed countries to cut emissions to about five per cent below their 1990 levels. A is wrong because 2004 is the year Russia ratified, not the year the treaty began. C and D are wrong because the protocol was already working by then; 2007 is remembered instead for the Bali road map. Exam tip: adopted in 1997, in force in 2005, first commitment period 2008 to 2012.

The correct answer is C, Odisha. Chilika is a shallow lagoon on the Bay of Bengal coast, separated from the sea by a sandy ridge and joined to it by a narrow mouth, which is why its water is brackish. It was among the first two Indian sites on the Ramsar List, it shelters the Irrawaddy dolphin, and the island of Nalabana within it is a bird sanctuary that fills with migratory birds in winter. Option A is wrong because the large lagoon of Andhra Pradesh is Pulicat, which is shared with Tamil Nadu and ranks second in the country. Option B is wrong because West Bengal is the land of the Sundarbans delta, not of a large lagoon. Option D is wrong because Tamil Nadu has the Point Calimere and Pichavaram wetlands and the southern part of Pulicat, but Chilika does not reach it.

The correct answer is B. The Montreux Record lists Ramsar sites where the ecological character has changed, is changing or is likely to change because of pollution, encroachment, siltation or other interference, so that the parties can direct attention and assistance there. From India, Keoladeo National Park and Loktak Lake are on it, while Chilika was entered and then removed in 2002 after restoration, the first Asian site to be taken off. Option A is wrong because a newly designated wetland simply joins the Ramsar List, which is a separate register. Option C is wrong because World Heritage status comes from a different treaty administered by UNESCO and has nothing to do with this record. Option D is wrong because Ramsar rests on wise use rather than exclusion, and fishing and grazing often continue on listed sites.

The correct answer is C, an atoll. Charles Darwin explained its formation: a fringing reef grows around a volcanic island, the island slowly subsides, the reef keeps growing upward towards the light, and in the end only a ring of reef and a lagoon are left where the island stood. Lakshadweep and the Maldives are the familiar examples. Option A is wrong because a fringing reef lies directly against the shore with little or no lagoon between, the commonest and youngest form. Option B is wrong because a barrier reef runs parallel to the coast but is separated from it by a wide, deep lagoon, the Great Barrier Reef off Queensland being the largest in the world. Option D is wrong because a patch reef is only a small isolated outcrop of coral inside a lagoon or on a shelf, not a landform type in this classification.

The correct answer is C, the Gulf of Khambhat. Its water is muddy, its tidal range is among the highest in the country and several rivers empty into it, so the clear, silt-free conditions that corals need are absent; it is known instead for tidal energy potential. Option A is wrong because the Gulf of Kachchh in Gujarat carries fringing reefs and a marine national park, the first of its kind in India. Option B is wrong because the Gulf of Mannar between Tamil Nadu and Sri Lanka has a chain of reef-bearing islands and was declared the country's first marine biosphere reserve. Option D is wrong because Lakshadweep is built of atolls, the ring-shaped reefs of the Arabian Sea, and is the classic Indian example of that reef type. The fourth true reef area, not listed here, is the Andaman and Nicobar Islands.