The 1920s are often called the roaring twenties because the decade was noted for

Change in cultural values

Explanation:

There was social and economic changes in the 1920s in the United States, it was called roaring twenties because of the changes in popular culture or traditional values of the decade. It was a time when many people disobeyed various forms of Prohibitions, new styles of dancing and dressing were incorporated, and what used to be moral standards were rejected.

jewish people, gypsies, and political opponents.

c. troops marched forward in close formation against newer, more accurate weapons