Which group's activities reflected a pattern of intolerance toward immigrants in the United States during the 20th century?

The Ku Klux Klan reflected a pattern of intolerance toward immigrants in the United States during the 20th century. The KKK targeted not only African Americans, but also immigrants, Catholics, Jews, and other minority groups, promoting a message of white supremacy and nativism. They used violence and intimidation to spread fear and enforce their discriminatory beliefs.