Explanation:

The Indian Wild Ass (Equus hemionus khur), also known as the Khur, is an endangered subspecies whose last remaining natural habitat in the world is the Little Rann of Kutch and its surrounding areas in Gujarat, India. This arid salt marsh ecosystem is unique to its survival. Option (1) Sundarban is a mangrove forest. Option (2) Western Ghats is a mountain range with dense forests. Option (4) Eastern Himalaya is a high-altitude region. None of these are suitable habitats for the Indian Wild Ass.