During the 1920s, the U. S. economy A. stagnated.
B. fluctuated constantly.
C. enjoyed prosperity.
D. saw some regions enjoy prosperity while others suffered deeply.

because it !

john maynard keynes developed new economic theories in response to the : b) great depression of the 1930s. his theories are so important that they are known as "keynesianism". in his works he supports the idea of a government with deeper involvement and intervention to end the great depression.

because of the war the westeners befriended japan and each other advance.