The correct option is B It had lost relatively few of its fighting forces and its economy was prosperous
European countries were the super powers , economically strong and colonially strong, with a huge army, but with the onset of world war , all the European nation's economy plummeted and new nations were formed and colonies were lost, and while all this was going on with Europe, America was on rise , it was economically strong and defeated the central powers, all the resources to entente were supplied by USA, and that's how it grew economically strong and then , USA could be the only that Europe might listen to because . entente might be biased in forming league, and hence ,USA played an important role in forming League of Nations.