Which post war action by the soviet union did the us see as a direct violation of the yalta agreement.

The correct answer is C. The Soviet Union established communist governments in Eastern European nations.

Explanation:

The Yalta Agreement included Stalin's agreement to permit free elections in Eastern Europe countries and to enter the war against Japan. In the end, Stalin broke his promise and established communist governments in Eastern European nations dominated by the Soviet Union.

These tensions escalated into the Cold War between the U.S. and the Soviet Union.