One way that the soviet union controlled eastern european areas was with the use of what?

The answer is C) Propaganda

The Soviet Union had an active presence in Eastern Europe.

The Soviets supported puppet governments, which signed treaties and pacts to  bring Soviet Union closer to the Eastern bloc.

The Soviet Propaganda machine used various mediums to instill a sense of fear and danger from the western borders.

This in turn, lead to the support of an active Soviet Military force in almost every Eastern European country.