In the given question, a statement of Assertion is followed by a statement of Reason. Mark the correct answer.

Assertion: The zamindars on the plains had to often purchase peace by paying a regular tribute to the hill chiefs.
Reason: The Paharias regularly raided the plains where settled agriculturists lived.

Both the Assertion and the Reason are correct and the Reason is the correct explanation of the Assertion.

With their base in the hills, the Paharias regularly raided the plains where settled agriculturists lived. These raids were necessary for survival, particularly in years of scarcity; they were a way of asserting power over settled communities; and they were a means of negotiating political relations with outsiders. The zamindars on the plains had to often purchase peace by paying a regular tribute to the hill chiefs.