What Accounts for the Tension Between Great Britain and the United

What accounts for the tension between Great Britain and the United States at the Yalta conference?

A) Churchill resented Roosevelt's private meetings with Stalin over proposed divisions of conquered Japanese territory in the Far East.
B) Churchill did not agree with Roosevelt's proposal to have the Soviet Union join the war against Japan.
C) Churchill and Roosevelt disagreed over the future status of Britain's overseas colonies.
D) Churchill resented an early suggestion by Roosevelt to allow communism in postwar Europe if the people supported it by popular referendum.