Introduction:
India has several protected areas that are established to conserve the natural resources and biodiversity of the country. Biosphere Reserves are one such type of protected areas that are established to conserve ecosystems and their biodiversity.

Explanation:
Biosphere Reserves are areas of terrestrial and coastal ecosystems that are internationally recognized under UNESCO's Man and the Biosphere (MAB) Programme to promote sustainable development. India has 18 Biosphere Reserves, out of which Nilgiri Biosphere Reserve is one.

Nilgiri Biosphere Reserve is located in the Western Ghats and Nilgiri Hills ranges of southern India. It was established in 1986 and covers an area of 5,520 square kilometers. The reserve includes parts of the states of Tamil Nadu, Kerala, and Karnataka and is home to several endangered species such as the Nilgiri tahr, lion-tailed macaque, and the Bengal tiger. The reserve also includes several national parks and wildlife sanctuaries such as Silent Valley National Park, Mudumalai National Park, and Bandipur National Park.

Other options:
Gir is the only natural habitat of Asiatic lions and is located in Gujarat. It is a wildlife sanctuary and a national park, but it is not a Biosphere Reserve.

Kanheri Caves are a group of caves located in the Sanjay Gandhi National Park in Mumbai. It is a protected archaeological site and a popular tourist attraction but is not a Biosphere Reserve.

Conclusion:
In conclusion, Nilgiri Biosphere Reserve is one of the 18 Biosphere Reserves in India and is located in the Western Ghats. It is established to conserve the ecosystems and biodiversity of the region and is home to several endangered species.