After the Chinese Entered the Korean Conflict in Support of North

After the Chinese entered the Korean conflict in support of North Korea,

A) Truman threatened to use the atomic bomb to end the conflict.
B) MacArthur called the North Koreans cowards and losers.
C) MacArthur and the UN troops drove the Communists back north across all of the Korean Peninsula and to the Chinese side of the Yalu River.
D) UN troops pushed the North Koreans and the Chinese back to the original dividing line at about the 38th parallel.
E) UN forces insisted that the Chinese pull out of the fight; when they did so, the North Koreans were helpless against the UN forces.