Which research source is an example of a primary source? a movie about Cold War-era chess

a textbook chapter about the Cold War

an article about the Cold War by an expert

a photograph taken during the Cold War era

a photograph taken during the cold war

although world war i began in 1914, the united states did not join the war until 1917. the additional firepower, resources, and soldiers of the u.s. to tip the balance of the war in favor of the allies. remaining neutral. when war broke out in 1914, the united states had a policy of neutrality.

c would be the correct !

hope this !

~bbgluver