Which statement about the brezhnev doctrine is true?
a. it called for soviet intervention in any communist country undergoing a rebellion. b. it allowed any communist nations to refuse soviet aid if the government voted against it. c. it instituted an embargo on any soviet goods going into or out of cuba. d. it supported revolutions such as those that happened in poland and hungary.

The correct answer is -

An example of this approach by Soviet leader Leonid Brezhnev can be seen in what happened in  Czechoslovakia in 1968.  Czechoslovakia's new leader, Alexander Dubcek, promoted reforms, and the people began to move away from communism. This became known as the "Prague Spring."   Seeing these actions as a threat to continued communist controlled, Brezhnev responded with force.  He sent 600,000 Soviet troops and put down any movement of revolution against communism in Czechoslovakia.

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