In the early 1800s, American Indians were allowed to live in the Great Plains because: A. white settlers did not want to farm this land.

B. they protected the United States from the Spanish.

ХC. they cleared the land for people coming west.

D. reservations were illegal in the existing states.

C. they cleared the land for people coming west.

Explanation:

As they were easily dispersed and allowed to live a nomadic life. The Spanish explorers were the first Europeans to conquer the plains village and cities. They used horses that enabled them to gain subsidence with relative ease. Thus here relation was named as horse culture. The plains became indigenous to these people as these tribal people used to live in the interior.

Dbecause i feel like that’s the correct answer

  the domino theory states that  if one country in a region came under the influence of communism, then the surrounding countries would follow in a  domino  effect.