RAS question
Which river is NOT part of the Arabian Sea drainage of Rajasthan?
Correct answer: (D) Banganga.
Banganga is not part of Rajasthan's Arabian Sea drainage; in this classification it belongs to the Yamuna-Ganga, Bay of Bengal side rather than the Mahi-Sabarmati-Luni group.
Explanation
Banganga is the exception because the question is asking for the river that does not belong to Rajasthan's Arabian Sea drainage. Banganga belongs to the Yamuna-Ganga system, linked with Bay of Bengal drainage, while Mahi, Sabarmati and Luni are treated as Arabian Sea drainage rivers. The official Banganga River Basin atlas also supports excluding it from the Arabian Sea group: Rajasthan Ground Water Department, Banganga River Basin describes Banganga as an east-flowing river and says that, after flowing through its basin, it drains into Ghana Lake near Bharatpur, forming an inland drainage system. That direction and drainage setting are unlike the three distractors, each of which is tied in the question data to the Arabian Sea side.
Why the other options are wrong
- (A) Mahi is not the exception because the question data states that it goes to the Gulf of Khambhat, placing it on the Arabian Sea drainage side.
- (B) Sabarmati is wrong for the same reason: it is stated to go to the Gulf of Khambhat, so it belongs with the Arabian Sea drainage rivers.
- (C) Luni is wrong because the question data classifies it as draining towards the Rann of Kutch, which is treated here as part of Rajasthan's Arabian Sea drainage.
Concept
This tests Rajasthan drainage-system classification, especially the distinction between Arabian Sea drainage and rivers outside that group. It recurs in RAS because river basins, drainage direction and regional physical geography are standard map-based facts.