How did the United States contribute to the Allied victory? Check all that apply.

a. By providing large numbers of reinforcements

b. By supporting the last major allied offensive

c. By boosting the morale of Allied troops

After a little research I determined that your answer is going to be: The United States contributed two main things: 1. Money. - The Allies were able to borrow $10.5 billion from sources in the United States, and $3.5 billion of that sum was raised before the United States entered the war. 2. Supplies.