The correct option is B IUCN
IUCN is the organisation for the conservation of nature, which publishes the Red List of threatened species or Red Data list which assesses the conservation of species. It is an international organisation founded in October 1948. Its headquarters are in Switzerland.
ICFRE is Indian Council of Forestry Research and Education which conduct forestry research, imparts forestry education, etc.
UNEP is United Nations Environment programme that coordinates its environmental activities, assisting developing countries in implementing environmentally sound policies and practices.
WWF is World Wide Fund for nature which works on issues regarding the conservation, research, and restoration of the environment.