It was primarily the "b. formation of the Vietcong in Vietnam" that led the Truman administration to expand the containment doctrine to include Asia, since this was seen as a threat to democratic principles in the west as well.
C: Jim Crow cut the close ties that had often existed in the antebellum South between black slaves and white owners.
Answer:
They use collective bargaining to gain rights for worker salaries and workplace safety.
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