Correct Answer: (d) Krishna and Tungabhadra
Solution:Krishna and Tungabhadra rivers flow in the region between Gulbarga and Vijayanagara Hampi. Under the rule of Harihara I, the Vijayanagara empire stretched from the Konkan coast in the West to Nellore and Kadapa in the East; and from the Krishna river in the North to the Kaveri river in the South. The many rivers flowing in this region (Krishna, Tungabhadra and Godavari, etc) made this region very fertile.