Answer:
World War II
Step-by-step explanation:
The initial plan used to rebuild the US economy after the Great Depression was the New Deal.
It included new restrictions on the banking industry and there were efforts to re-inflate prices that were at a very low point.
By the late 30's the US economy had recovered somewhat. However, it only reached full employment when the US entered the World War II after the Pearl Harbor bombings.
So the correct answer is:
World War II