Which problem did the entry of the American Expeditionary Forces (AEF) into
World War I help solve?
O A. Russia had pulled out of the war, leaving the remaining Allies at a
disadvantage.
B. Trench warfare meant progress was slow and many battles were
stationary.
OC. Great Britain had blockaded German ports while the United States
traded with all sides.
OD. Germany had been forced to fight a two-front war.