The US becomes the world's biggest creditor at this time. Not D
Germany suffered the most fault of the war.. it's why they got punished the most
German currency was facing hyper inflation as they tried to pay for their debts. It was so bad that a million marks were worthless in comparison to the US dollar.
The early aggression of France(linhet policy I think) on Germany did not help either, but may have avoided ww2. The occupation of Rhineland hurted Germany and France even more when German workers were put on resistance by french military.
It can not be A or C
It is B, since we know that the 10 years of bubble economic growth after WW1 was fueled by a circle of irresponsible loans that caused the Great Depression.