The correct answer is:
D) isolationist sentiment was strong in the United States.
Isolationism had spread over progressives and conservatives, business owners and peace activists alike. Without an ordered opposition from internationalists, their doctrine triumphed and even Roosevelt seemed to accept their strength in Congress. The outbreak of war in 1939 hardly made public opinion shift from advocating full neutrality to backing limited U.S. assistance to the Allies, far from an actual intervention in the war.