The post-impressionist artists discussed in the text found inspiration from all of the following sources except
a. non-western cultures
b. folk art
c. classical art
d. medieval art

shows criminal activity in the U.S. had increased greatly.

Explanation:

There is no "crime wave" in real life, however, a wave suggest a sudden accumulation of water that in turn crashes onto a land form. This would be the case of a "crime wave". There may be a steady and low amount of crime before and after, but during the 1930s, the amount of crime in the US rose sharply.

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