The buffalo was a mainstay of the Native Americans of the

old west

Explanation:

Native Americans depended largely on hunting and agriculture for their food supply. Times when the crops became scare, their primary source of food was buffalo. Buffalo for Native Americans residing on the plain regions was a mainstay. Buffalo's' meat helped in meeting the basic food requirement of the people. The invention of guns and more advanced weapons helped to hunt buffalo more easily. Also, buffalo was found in abundance which made it the most easily available food source. With enormous hunting down of the buffaloes, the number of the buffaloes decreased. They reached to the point of extinction by the end of 1990s.

c-three

explanation:

legislative, executive and judicial