Answer:
I think the correct answer is C. 15th Amendment.
Step-by-step explanation:
The 15th Amendment, which sought to protect the voting rights of African American men after the Civil War, was adopted into the U.S. Constitution in 1870 by declaring that the "right of citizens of the United States to vote shall not be denied or abridged by the United States or by any state on account of race, color, or previous condition of servitude."