The correct option is (d) Western Ghats.
Explanation
The Great Indian Hornbill (Buceros bicornis) is a large arboreal bird species native to the Indian subcontinent and Southeast Asia. Its distribution is strictly linked to specific vegetation types, primarily tropical evergreen and moist deciduous forests. These birds require vast stretches of forest with tall, old trees for nesting and a continuous supply of fruits, particularly figs.
Option Analysis:
- (a) Sand deserts of northwest India: Incorrect. This region is characterized by arid, xerophytic vegetation. It lacks the dense canopy and fruiting trees essential for Hornbills. This terrain is the natural habitat of the Great Indian Bustard.
- (b) Higher Himalayas of Jammu and Kashmir: Incorrect. The higher Himalayas feature temperate, alpine, and cold desert vegetation. Hornbills are restricted to lower altitudes (foothills) where tropical and subtropical forests thrive.
- (c) Salt marshes of western Gujarat: Incorrect. The Rann of Kutch consists of saline wetlands and open plains, suitable for the Indian Wild Ass and Flamingos, but completely unsuitable for forest-dwelling birds like the Hornbill.
- (d) Western Ghats: Correct. The Western Ghats contain extensive tropical evergreen and moist deciduous forests that provide the necessary canopy and food sources. Consequently, this region is one of the primary natural habitats for the Great Indian Hornbill in India.
Key Takeaway:
The Great Indian Hornbill has a disjunct distribution in India, found primarily in the Western Ghats and the Northeast (Himalayan foothills). They are indicators of healthy, mature tropical forests.