What was the relationship between the civil rights movement and the labor union movement during the 1940s?

A) Civil rights organizations generally distanced themselves from labor activism,which they regarded as a needless distraction,and even dangerously radical.
B) Despite efforts by civil rights organizations to encourage the unionization of black workers,the entrenched racism of the industrial workplace proved too strong to overcome.
C) Labor unions often worked closely with civil rights organizations,and also provided early training in the forms of mass protest which would be employed in the later civil rights movement.
D) The civil rights movement and the labor union movement were actively hostile toward each other because each movement saw the other as an obstacle against desired change.