Which of the following rivers is having the largest river basin area in Rajasthan?

Correct option is C

 
According to the information available, the river with the largest river basin area in Rajasthan is the Banas river. So the answer is (c). 
Explanation: 
The Banas river basin covers the largest area within Rajasthan, draining a catchment area of 45,833 square kilometers. 
Key points about the rivers mentioned:
· Banas: Largest river basin in Rajasthan. 
· Chambal: While having a large catchment area in Rajasthan, it is not the largest compared to the Banas. 
· Luni: Considered the largest river system in western Rajasthan but not the largest basin area overall. 
· Mahi: Not a major river in Rajasthan.