Which clause allowed individuals to vote based on their grandfather's voting history, effectively disenfranchising many African Americans?

The grandfather clause allowed individuals to vote based on their grandfather's voting history, effectively disenfranchising many African Americans by creating a legal loophole that exempted white voters from literacy tests and other requirements that were imposed on Black voters. This clause was designed to ensure that if someone's grandfather had been eligible to vote prior to the Civil War, that individual could vote regardless of their own circumstances or qualifications.

This mechanism was part of a broader set of Jim Crow laws that sought to maintain white supremacy in the South after the Reconstruction era. By implementing such clauses, Southern states could uphold discriminatory practices that effectively marginalized Black voters while allowing many white citizens to bypass obstacles that had been set in place.

The other choices relate to voting restrictions but do not specifically reference the grandfather clause or its disenfranchising effects on African Americans.