Which of the following was not a factor in american prosperity following WW1?

A) America gained European territory after that war and was able to export products to Europe and Africa without economic barriers.

B) america did not suffer the destruction that Europe experienced during war.

C) American industry was modernized and able to produce more products in less time.

D) America transitioned from a debtor nation to a creditor nation (was owed more money from other nations than what it owed to other nations)

Answer is A. America didn't gain European territory, they loaned money to Germany, in order to pay repairment debts that Germany had with other countries and these, in turn, paid their debts to America, in dollars. Prior to the war, some industries were able to export without restrictions, but, with the declaration of war, that ended.

The following was not a factor in American prosperity following WWI: America gained European territory after that war and was able to export products to Europe and Africa without economic barriers. After World War I the US continued enforcing high tariffs, which was one of the main sources of revenue for the country. When a country has tariffs on imports, it means that it's products have tariffs on the given country's exports. This is because there wasn't a free trade agreement between the US and Europe. On the other hand, the world took a protectionist approach after WWI by enforcing high tariffs. Also, after WWI the gold standard was abandoned despite the efforts that were made to reenforce it. Finally, WWI put restriction on the movement of financial capital. With the end of WWI, African countries were granted their independence and the United States did not gain any European territory.

Statements B, C, and D are true.