What was the Domino Effect? A. when one country fell to capitalism then the next would
B. when one continent falls to communism the next would
C. when one country explodes they all would
D. when one country fell to communism the next would

The answer is D.

Explanation:

So when the US was at war with the USSR in the Cold war this was a theory that basically said if communism topples a government then the neighboring country would also be toppled and the naming comes from the apparent domino effect as in one tumbles and the next one tumbles.

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