During the Berlin crisis, both the United States and the Soviet Union feared that the other side would try to take control of the entire city of Berlin.
allow the people of Berlin to decide on the city's future.
destroy Berlin because it had been the capital of Nazi Germany.
O move the city of Berlin to a location in West Germany.

a) try to take control of the entire city of Berlin.

Explanation:

This question placed it as "BOTH (emphasis added) the United States and the Soviet Union...". The only answer that makes sense in this case is a), as Berlin is Germany's capitol, and that almost all jurisdiction lies within the city. For it to fall in one or another hands can decide the course of whether or not Germany follows a more socialist government, or a representative/democratic one. As Germany by itself was one of the larger and major countries in Europe, it can lead to either the bulwark against the expansion of Communism, or the Domino theory if failed.

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