Under the Terms of the Yalta Agreement, What Did the Russians

Under the terms of the Yalta Agreement, what did the Russians agree to do?

A) Pull out of occupied Poland at the end of the war.
B) Carry out free elections in Eastern Europe within three months of the end of the war.
C) Receive control of the Eastern European countries that were on their border.
D) Oversee elections in Eastern European countries as soon as reasonably possible.
E) Join the United States in the Pacific theater within three months.