Out of the given options, the statement that says 'America gained European territory after that war and was able to export products to Europe and Africa without economic barriers' was not a factor in American prosperity following World War.
Answer: Option 3
Step-by-step explanation:
In neither of the two world wars America held any of the European or African territories to themselves that they had won in the war. The United States prospered even after the World Wars.
Because it didn't serve as the battlefield for the World War as most other participating countries did.