Question

McCarthyism was successful because Americans feared

a.

the Cold War.

c.

Communism.
b.

Soviet domination.

d.

all of the above.

Answer 1

McCarthyism was successful because Americans feared "all of the above" since tensions were extremely high during this period of the Cold War. People thought communism would take over the world. 

Answer 2

Given that it was all about communism and the Soviet Union, I'd say your answer will most likely be D.