The correct answer is A) countries trapped behind a large impenetrable wall.
The image that Churchill wanted to create with the phrase "iron curtain" was countries trapped behind a large impenetrable wall.
The Iron Curtain was a term after World War II that identified the political, economic, military and physicological barrier imposed by the Soviet Union to keep enemies away from Communist countries in Eastern Europe such as East Germany, Poland, Hungary, Bulgaria, and Romania.
Great Britain Prime Minister, Winston Churchill, used this term during a speech on March 5, 1946, in Fulton, Missouri, in the United States.