In What Way Was Operation Overlord a Turning Point in the War

In what way was Operation Overlord a turning point in the war?

A) It opened a western front in the war around the same time the Soviets advanced on Germany from the east.
B) It led to the defeat of Britain and, as a result, delayed the ability of the United States to stage troops near Europe.
C) It led to the defeat of Axis forces in North Africa and, due to the certainty of the Allies, was one of the least complex invasions.
D) It led to the fall of Mussolini's regime in Italy, opening a door for Allied forces to Germany from the south.
E) It brought China into the war against Japan, making it impossible for Japan to continue to dominate the Pacific.