Concept:The Ramsar Convention is an international treaty focused on the conservation and sustainable use of wetlands worldwide.Explanation:The main aim of the Ramsar Convention is to protect wetlands and promote their wise use. It was signed in Ramsar, Iran on 2nd February 1971 and came into force on 21st December 1975. Wetlands include marshes, lakes, rivers, and coastal areas that are important for biodiversity and water regulation. The treaty encourages countries to designate and manage wetland sites of international importance. It does not specifically target biodiversity in general, global warming, or climate change as its primary goal.Answer:A. Conservation of wetlands