How did the justice department under a mitchell palmer respond to this fear?

Hunted down suspected communists, anarchists and socialists, and jailed them.

Explanation:

The Bolshevik revolution in Russia and fear that migrants from Russia and Easter, Southern Europe wanted to over throw the US government was also a major factor for Red Scare. The Palmer raids were conducted during the first Red Scare.

In June 1919 Eight bombs exploded in eight american cities. One of the bombs damaged home of US Attorney General Mitchell Palmer. After this he led a campaign against communists, political radicals and anarchists, it was known as Palmer Raids. Headquarter of various radical organisations and homes of foreign residents and immigrants were raided during 1919-1920 and more than 10,000 suspects were detained without hearing and more that 600 immigrants were deported.

i am pretty sure the awsers is d.

b. andrew