Indri indri occurs in
(a) India
(b) Mauritius
(c) Fiji
(d) Madagascar

Hint: Indri indri is an endangered species. It is losing its rainforest habitat for fuel, timber, and slash-and-burn agriculture. Destruction is occurring even in protected areas. Hunting of indris is taboo to the local people, although occasionally one is killed for food.

Complete answer:
The indri indri is also called the babakoto. It is endemic to Madagascar. It is one of the largest living lemurs. It has a black and white coat. It maintains an upright posture when climbing or clinging. It is monogamous and lives in small family groups, moving through the canopy. It is purely herbivorous, feeding mainly on leaves but also seeds, fruits, and flowers. The groups are quite vocal, communicating with other groups by singing, roaring, and other vocalizations. It is a diurnal tree-dweller related to the sifakas. The main threats faced by the indri are habitat destruction and fragmentation due to slash and burn agriculture, fuelwood gathering, and logging. It is also hunted despite taboos against this. The International Union for Conservation of Nature has rated its conservation status as “Critically endangered''.

Additional Information:
- The indri is a vertical clinger and leaper and thus holds its body upright when traveling through trees or resting in branches.
- It has long, muscular legs which it uses to propel itself from trunk to trunk. Its large greenish eyes and black face are framed by round, fuzzy ears that some say give it the appearance of a teddy bear.
- It is revered by the Malagasy people and plays an important part in their myths and legends with various stories in existence accounting for its origin.
So, the correct answer is ‘(d) Madagascar'.

Note:
- Unlike any other living lemur, the indri has only a rudimentary tail. The silky fur is mostly black with white patches along with the limbs, neck, crown, and lower back.
- Different populations of the species show wide variations in color, with some northern populations consisting of mostly or entirely black individuals.
- The face is bare with pale black skin, and it is sometimes fringed with white fur. Due to these color variations, Colin Groves listed two subspecies of the indri in 2005.