সঠিক উত্তর হচ্ছে: IUCN
ব্যাখ্যা: The International Union for Conservation of Nature (IUCN) is a membership Union composed of both government and civil society organisations. It harnesses the experience, resources and reach of its more than 1,300 Member organisations and the input of more than 15,000 experts. This diversity and vast expertise makes IUCN the global authority on the status of the natural world and the measures needed to safeguard it. এর সদরদপ্তর গ্ল্যান্ড, সুজারল্যান্ডে। Source: IUCN website.