Which amendment granted African American men the right to vote?

The correct choice is the 15th Amendment, which explicitly states that the right to vote cannot be denied or abridged based on race, color, or previous condition of servitude. Ratified in 1870, this amendment was a significant milestone in the struggle for civil rights, specifically targeting the systemic disenfranchisement of African American men following the Civil War.

In the context of the other amendments, the 13th Amendment abolished slavery, and while it was a crucial step toward freedom for African Americans, it did not grant voting rights. The 19th Amendment, ratified in 1920, extended the right to vote to women, but it does not pertain to African American men specifically. Lastly, the 24th Amendment, passed in 1964, eliminated poll taxes in federal elections and further protected voting rights, but it came much later than the 15th Amendment and was aimed at removing barriers to voting that still affected various groups, including African Americans.

Thus, the 15th Amendment is the landmark legislation that directly aimed to ensure that African American men could exercise their right to vote after years of oppression and discrimination.