Answer : 3. "Krishna "
Explanation :

The Krishna River is a peninsular river that rises from a spring near Mahabaleshwar and flows for about 1400 km and reaches the Bay of Bengal. The Tungabhadra, the Koyana, the Ghatprabha, the Musi and the Bhima are some of its tributaries. Its drainage basin is shared by Maharashtra, Karnataka and Andhra Pradesh. Some of the other major peninsular rivers which flow eastwards and drain into the Bay of Bengal are the Mahanadi, the Godavari, the Krishna, and the Kaveri. Nagarjuna Sagar Dam was built across the Krishna river at Nagarjuna Sagar where the river is forming a boundary between Nalgonda district of Telangana state and Guntur district of Andhra Pradesh state in India.