which explains how suffrage was granted to black men in the United States

through a convention
through the U.S. Constitution
through the voting rights act of 1965
through a constitutional amendment

Suffrage, or the right to vote, was granted to black men in the United States through a constitutional amendment. Specifically, the 15th Amendment to the U.S. Constitution, ratified in 1870, granted African American men the right to vote. The amendment states: "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." This amendment was a significant step in the fight for civil rights and political equality for African Americans.