Which of the following rivers is famous for its rift valley drainage?

The correct answer is B) Damodar. The Damodar flows through a graben, a rift valley formed by faulting in the Gondwana sediments between the Chota Nagpur plateau and the Rajmahal hills. This rift-valley course is why the river is so closely associated with the valley's coal fields and its mineral wealth, and the Damodar Valley Corporation, set up in 1948 as India's first multipurpose river valley project, was built around it. The core concept is that a rift valley is a down-faulted trough, and the Damodar is the classic Indian example.

• Chambal is wrong. It rises in the Vindhyan escarpment and is famous for its ravines and badlands, not a rift valley.
• Gandak is wrong. It is a Trans-Himalayan river that cuts through Himalayan gorges in Nepal and joins the Ganga near Hajipur. Its geography is Himalayan, not rift.
• Ramaganga is wrong. It is a Kumaon-Garhwal Himalayan tributary of the Ganga, known for the Kalagarh dam, with no rift-valley feature.

For Mains GS-I (Geography, Physical and Economic) and GS-III (Infrastructure and river valley projects), the Damodar case links rift valleys, coal and river valley planning.

Trap: aspirants pick Chambal because of its famous ravines, confusing erosional badlands with a tectonic rift valley.