Answer:
C. Grandfather clauses.
Step-by-step explanation:
C. Grandfather clauses were created after the implementation of poll taxes and literacy tests in order to increase the number of white voters. These clauses exempted individuals from these requirements if their ancestors had voted prior to the Civil War, effectively allowing many white voters to avoid the restrictions while still preventing African Americans from voting. This was a discriminatory tactic aimed at suppressing the voting rights of Black citizens in the United States.