Answer:
It prohibited the formation of a Communist Party in the United States.
Option A is not correct with reference to the mccarren act.
Step-by-step explanation:
The act requires the communist organisations to register with the government of the United States to enquire people involving in subversive activities or enhancing the establishment of totalitarian dictatorship.
The members of this group cannot become American citizens in some cases, they were denied Passport. President Truman vetoed against this act as he considered it unconstitutional, although Congress overrode his veto. The critics of this act believed that the act posed a risk to the first amendment rights of "freedom of speech and association".