Why did the united states send several billion dollars to aid the nationalists in china?

American leaders feared that a Nationalist defeat would create a communist superpower.

(d) rivers.

explanation:

civilizations developed around rivers because their waters provided places to hunt and fish. also, as the rivers flooded, the lands around them became fertile. this allowed them to support farming. this is especially true of the nile river, which flooded the same time each year.

its c not d   tell me if that´s correct