Why did the Southern states reluctantly agree to allow blacks to vote?

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As a result of intimidation, violence, and racial discrimination in state voting laws, a mere 3 percent of voting-age black men and women in the South were registered to vote in 1940. In Mississippi, less than 1 percent were registered. Most blacks who did vote lived in the larger cities of the South.

By not having the power of the ballot, African Americans in the South had little influence in their communities. They did not hold elected offices. They had no say in how much their taxes would be or what laws would be passed. They had little, if any, control over local police, courts, or public schools. They, in effect, were denied their rights as citizens.

Attempts to change this situation were met with animosity and outright violence. But in the 1950s, the civil rights movement developed. Facing enormous hostility, black people in the South organized to demand their rights guaranteed in the U.S. Constitution. They launched voter registration drives in many Southern communities. This set the stage for great changes in the 1960s, but not without tragedy. Medgar Evers, the black veteran stopped by a white mob from voting, became a civil rights leader in his native Mississippi. Because of his civil rights activities, he was shot and killed in front of his home by a white segregationist in 1963.

Explanation:

option d is correct. corroborated sources of historical evidence   is necessary to validate a claim about an event in history.

historians tend to use written sources, but audio and visual materials as well as artifacts are important objects that supply information to modern historians.

historical sources are usually divided into two categories: primary and secondary sources. depending on the historian's intent, some sources shift their designation. determining what type of sources toimplement, and the level of credibility and reliability of those sources, is a significant step in critical thinking for the historian.

explanation: