It’s the scape of the land
D. Contain the spread of Communism in every region of the world
The domino theory said that if one country falls to Communism, then the nations it associates with will turn to Communism as well. So, the solution for this was try to contain Communism so it wouldn't spread.
The Powhatan Confederacy was a group of different Native American tribes who lived in Virginia. This group generally had tense interactions with the British settlers, because the British settlers believed that the Powhatan Confederacy owed it to them to help them with the food supply, as the British settlers had trouble having sufficient food for their community.