In the 1920s, the anti-defamation league brought national attention to the racism of which group?

It was founded in 1913 by  B'nai B'rith. It is a Jewish service organization that is created in the US whose advocacy is to stop defamation among Israel people. The ADL, however, extends its purpose to all people. The goal is as stated by the  ADL is to "fight anti-Semitism and all forms of bigotry, defend democratic ideals and protects civil rights for all", doing so through "information, education, legislation, and advocacy."  One of the major cause is to promote freedom of all religions. 

Monopolies and trusts began to increasingly gain control over the United States' economy as the country entered the gilded age. Consequentially, more factories were created, which then resulted in the necessity of cheap employment from unskilled workers, and ultimately expanded organized labor.

Explanation: