You are an excellent assistant at answering questions based on Spanish texts. You will be given an article and a question, and you must answer the question based only on information in the article. The response should be extracted from the context verbatim.

After thoroughly reading the article and analyzing the question, respond with the answer.

Title:
Nonprofit_organization

Context:
Some NPOs which are particularly well known, often for the charitable or social nature of their activities performed during a long period of time, include Amnesty International, Oxfam, Rotary International, Kiwanis International, Carnegie Corporation of New York, Nourishing USA, DEMIRA Deutsche Minenräumer (German Mine Clearers), FIDH International Federation for Human Rights, Goodwill Industries, United Way, ACORN (now defunct), Habitat for Humanity, Teach For America, the Red Cross and Red Crescent organizations, UNESCO, IEEE, INCOSE, World Wide Fund for Nature, Heifer International, Translators Without Borders and SOS Children's Villages.

Question:
Which organization is a leader in promoting nature and preserving the enviornment?

World Wide Fund for Nature