Answer:
D. House Un-American Activities Committee.
Explanation:
Because the Cold War escalated, it became recognized as the Red Scare, the hysteria over the supposed danger posed by communists in the USA.
The Government of the United States responded by establishing the House Un-American Activities Committee (HUAC), tasked with detecting communist dangers to the U.S.
HUAC was founded in 1938 to prosecute suspected treachery and subversive behavior by private individuals, public workers and institutions accused of communist connections.
Americans who are accused of having ties with the Communist Party will be prosecuted in court.