What was a major cause of nativist attitudes during the 1920s?

A. emergence of the Second Ku Klux Klan

B. the growing diversity of languages, customs, and religions in the US

C the controversial trial of Nicola Sacco and Bartolomeo Vanzetti

D. the intense debate surrounding teaching evolution in schools

What caused the development of nativism in the 1920s? ... nativists thought this meant fewer immigrants should be let in the country. some people involved in postwar disputes were immigrant anarchists and socialists, who many americans believed were actually communists.

Option C, the controversial trial of Nicola Sacco and Bartolomeo Vanzetti, is the right answer.

Explanation:

During the early phase of the 20th Century, there was an influx of immigrants in the United States which gave rise to nativism in America.

This immigration led to expanding the diversity of belief, culture, language etc. causing great concern and tension in the minds of the local residents or the natives. This also led to the adoption of the racial approach towards the emigrants.

Nativism reached its zenith during the trial of Bartolomeo Vanzetti and Nicola Sacco. They were two Italian immigrants who were accused of robbery and murder. Despite the lack of convicting evidence, the Jury declared them guilty and ultimately executed on August 23rd, 1927.