Answer: C) Increased CO2 absorption Explanation: Ocean acidification occurs when CO2 from the atmosphere dissolves in seawater, forming carbonic acid. This leads to a decrease in the pH of the ocean, adversely affecting marine life, especially organisms with calcium carbonate shells and skeletons.

Answer: C) Sulfur dioxide (SO2) Explanation: Greenhouse gases are those that trap heat in the Earth’s atmosphere, contributing to the greenhouse effect. Methane, nitrous oxide, and carbon dioxide are all greenhouse gases, while sulfur dioxide is primarily an air pollutant and not a greenhouse gas.

Answer: C) Paris Agreement Explanation: The Paris Agreement, adopted in 2015, is an international treaty that seeks to limit global warming to well below 2°C, preferably to 1.5°C, compared to pre-industrial levels. The Kyoto Protocol and the Montreal Protocol also address environmental issues but focus on different aspects like ozone depletion and specific greenhouse gas emissions.

Answer: A) Areas with a high level of endemism Explanation: Biodiversity hotspots are regions that are rich in endemic species but are also experiencing significant habitat loss. These areas are critical for conservation efforts to preserve the planet’s biodiversity.

Answer: C) Yamuna Explanation: The Yamuna River is one of the most polluted rivers in India due to industrial discharge, untreated sewage, and other pollutants. Major cities like Delhi contribute significantly to its pollution levels, making it a critical environmental concern.