What was the purpose of the palmer raids?
to arrest people who were thought to be immigrants
to arrest people who were afraid of communism
to arrest people who were thought to be radicals
to arrest people who went on strike for higher wages

To arrest people who were thought to be radicals

Explanation:

The Palmer raids occurred in 1919 and 1920 during the first Red Scare. They were conducted in order to arrest radical leftists and were usually against Italian and Eastern European immigrants. These were most aggressive against anarchists and communists and resulted in their deportation. This paved the road for later ethnic and racial deportations.