Why did new art movements develop in the years following world war 1?

B

Explanation:

The aftermath of WW1 usually left the public confused on who/what to believe. A lot of artists described their opinions on the war and its destruction and developed ideas centering around peace, and anti-materialism. Since a lot of artists were in the war, they also described their horrifying experiences through their art.

Source: https://www.metmuseum.org/blogs/now-at-the-met/2017/world-war-i-and-the-visual-arts-introduction