The correct option is D Conserve all the sites through ecosystem approach and allow their simultaneous sustainable use
The Ramsar Convention (The Convention on Wetlands of International Importance, especially as Waterfowl habitat), named after the town of Ramsar in lran, is an international treaty for the conservation and sustainable utilisation of wetlands, i.e. to stem the progressive encroachment on and loss of wetlands now and in the future, recognising the fundamental ecological functions of wetlands and their economic, cultural, scientific, and recreational value.