Answer: Assam and West Bengal
Notes: The Sankosh River flows between the Indian states of Assam and West Bengal, serving as a natural boundary. This important river also has tributaries in Bhutan. Originating in the glacial regions of the eastern Himalayas, it merges with the Brahmaputra River, contributing to its sheer volume and making it a significant part of the region's ecosystem. This river is crucial for local inhabitants and has great strategic importance.
