In the following passage, some of the words have been left out. Read the passage carefully and select the correct answer for the given blank out of the four alternatives.
India handled the problem of the cat preying on goats, sheep, donkeys and other animals by roping ________ communities in conservation, and compensating them for any losses. An insurance programme in _________ residents of a part of Spiti Valley in Himachal Pradesh ________________ also worked well. New research _____________ that even when wild prey is available, the attacks on livestock by snow leopards have ________________ been on the rise.
An insurance programme in _________ residents of a part

Options

A. which
B. what
C. when
D. whereas

Answer

C