Who were the main Allied Powers during World War II?

The main Allied Powers during World War II were comprised of a coalition that included the United States, the United Kingdom, the Soviet Union, France, and China. This alliance formed in response to the Axis Powers—a group primarily consisting of Germany, Italy, and Japan.

The significance of these specific nations lies in their pivotal roles during the war. The United States provided extensive military resources and support after entering the war following the attack on Pearl Harbor in 1941. The United Kingdom was engaged in fighting against Axis forces from the war's outset in 1939. The Soviet Union, after initially signing a non-aggression pact with Germany, joined the Allies following Operation Barbarossa—the German invasion of the Soviet territory in 1941. France, despite its swift fall to German forces in 1940, had a significant government-in-exile actively supporting Allied efforts, and China was engaged in a prolonged battle against Japanese invasion and occupation.

The other options listed do not accurately represent the main Allied Powers, as they either include countries that were not part of the alliance or omit key allies essential to the combined military effort against the Axis Powers.