Which of the following caused great resentment in post-World War I Germany?

A. German money increasing in value year after year

B. The war reparations that hadn't been paid by France

C. The war reparations that had to be paid by Germany

D. German-speaking Austrians moving to Germany

C. The war reparations that had to be paid by Germany

I could say that the correct answer is C The war reparations that had to be paid by Germany.

Reparation is connected to the payments Germany had to do after the damages of the war. It was required by the Treaty of Versailles. This was possible because Germany accepted they have caused the war so they were responsible for all the damages.