In the aftermath of the world war 2 what happened to the US economy

B. There was a major sustained expansion.

Explanation:

There was a major sustained expansion. The war industry led to a huge growth in the GDP, and the fact that many foreign markets needed our goods meant that exports were very strong.

America's involvement in World War II had a significant impact on the economy and workforce of the United States. Our involvement in the war soon changed that rate. American factories were retooled to produce goods to support the war effort and almost overnight the unemployment rate dropped to around 10%.