The correct answer is: "voter segregation".
The Voting Rights Act was issued in 1965, seeking to effectively stop racial discrimination in voting, in the middle of the peak of the civil rights' movement. It is a landmark federal legal instrument which was enacted to enforce the voting rights that were already contained in the US Constitution, in the Fourteenth and Fifteenth Amendments, ratified in 1868 and 1870 respectively. These two amendments had been circumvented by numerous states for almost a century by approving measures which indirectly enhanced segregation and prevented racial minorities from participating in elections.
