Which term refers to the policy of containing communism and preventing its spread into more countries?
a. the iron curtain
b. the marshall plan
c. the truman doctrine
d. the berlin wall

It was the Truman Doctrine.

The Iron Curtain was the metaphorical barrier that seemed to split the Eastern Bloc from Western Europe. It was first mentioned by Churchill. The Berlin Wall was the physical embodiment of this "Curtain" that was constructed by the USSR to prevent Eastern Europeans from migrating. The Marshall Plan sent $13 billion to European nations to help them rebuild after WWII. The Truman Doctrine was specifically put in place to contain communism by aiding nations that were "at risk" so they would not turn to communism to solve their problems.

Ithink the answer is c