The correct ansswer is the American policy of trying to stop the spread of global communism.
After World War II, the United States and Soviet Union emerged as global superpower. These two countries had vastly different ideas on what economic and political systems should be implemented within a society. The Soviet Union was in favor of a communist system, which was almost completely opposite of the American system of capitalism.
This is why the United States adopted a policy of containment during the Cold War era.The American government felt that the communist system was ineffective, so they wanted to stop it from spreading to other countries all over the world.
