The correct answer is A) True.
It was true that most of McCarthy's accusations were false.
We are talking about Republican Senator from Wisconsin, Joseph McCarty. During the Cold War years -by 1950s. he accused many government employees and military officials of the United States to have connections with Communists. This persecution time was known as the "Red Scare," and ruined the reputation of many people. Later, it was proved that McCarty's accusations were just opinions and he could provide any support to its claims.