The correct answer is true.
It is true that the CIO, which had a long history of Communist members, purged over 1 million workers from its ranks during the Red Scare.
CIO stands for Congress of Industrial Organizations. Founded by John L. Lewis in 1938, in Pittsburgh, Pennsylvania, he became the first President. It started with 4 million members and by 1945, membership in the number of workers had risen to 6 million. However, during the Red Scare, -the accusations of Republican Senator for Wisconsin's Joseph MacCarthy about Communists infiltration in the federal government- the CIO had to expel 11 affiliated unions for having ties with Communists.
