Why Correct: The Ramsar Convention on Wetlands was signed on 2 February 1971 in Ramsar, Iran, establishing the international framework for wetland conservation and wise use.
Distractor Analysis: Earth Summit refers to the 1992 UN Conference on Environment and Development in Rio de Janeiro. Belem Declaration (1988) established the Amazon Cooperation Treaty Organization. Botanical Congress is the International Botanical Congress that meets every six years to discuss plant science.
Takeaway: World Wetlands Day is celebrated annually on 2 February, marking the date the Ramsar Convention was adopted in 1971.