The correct answer is All the above. Explanation & Key Takeaways: • Earth Summit: • The Rio Summit 1992 is also called the Earth Summit. • It was attended by 170 states, thousands of NGOs and many multinational corporations. • There was a consensus on combining economic growth with ecological responsibility, also known as ‘sustainable development’. • The Rio summit produced conventions regarding climate change, biodiversity, forestry and recommended a list of development practices called Agenda 21. Hence, a is correct. • Kyoto Protocol: • The Kyoto Protocol was an international treaty signed in 1997 to extend the UN Framework Convention on Climate Change (1992). • It committed state parties to reduce greenhouse gas emissions and arrived at a scientific consensus on its role behind climate change. Hence, b is correct. • It took place at Kyoto, a prefecture in the region of Kasai, Japan. • UNFCCC: • The United Nations Framework Convention on Climate Change (UNFCCC), was signed in 1992 at the United Nations Conference on Environment and Development also known as the Earth Summit, the Rio Summit or the Rio Conference. Hence, c is correct. • The UNFCCC entered into force on 21st March 1994 and has been ratified by 197 countries. • Ramsar Convention: • It is an international treaty for “the conservation and sustainable use of wetlands”. • It is also known as the Convention on Wetlands. • It is named after the city of Ramsar in Iran. • The Convention was signed on the 2nd of February 1971. • At the centre of the Ramsar philosophy is the “wise use” of wetlands. • Wise use: maintenance of ecological character within the context of sustainable development. Hence, d is correct.