The Palmer Raids of the 1920s were a response to

Aorganized crime developing after Prohibition
Bgovernment corruption as illustrated in the Teapot Dome Scandal
Cfears of communism following the Russian Revolution
Dthe reemergence of the Ku Klux Klan during the 1920s
Ethe reemergence of trusts following the First World War

Verified Answer :

The Palmer Raids of the 1920s were a response to "(C) fears of communism following the Russian Revolution," since this was the time of the "Red Scare" in American, where there was a general fear of radical leftist points of view. 

Answer:

C. the rise of nativism after World War I

Explanation: