What was the "Iron curtain" the Winston Churchill referred to?

Answer:C

Explanation:the imaginary line that seperated communist countries from free countries in Europe

The "Iron Curtain" that Churchill referred to is the fact that ultimately the Soviet Union controlled Eastern Europe.

Or in other words, "the political, military, and ideological barrier erected by the Soviet Union after World War II to seal off itself and its dependent eastern and central European allies from open contact with the West and other non-communist areas".