Answer: (Detailed Solution Below)
Option B: A-4, B-3, C-2, D-1
Detailed Solution:
The correct answer is “A-4, B-3, C-2, D-1”.
A. Bhakra - 4. Sutlej
B. Hirakud - 3. Mahanadi
C. Idukki - 2. Periyar
D. Nagarjuna Sagar - 1. Krishna