What means were available to disenfranchise blacks in America to fight segregation?

In the Southern states of the United States, on the other hand, legal segregation in public facilities was current from the late 19th century into the 1950s. (See Jim Crow law.) The civil rights movement was initiated by Southern blacks in the 1950s and '60s to break the prevailing pattern of racial segregation.

Your answer is d)magnesium