After the Civil War, the federal government began to extend civil rights to African Americans by

After the Civil War, Congress and the states adopted the Reconstruction Amendments to expand African Americans’ rights. The 13th Amendment abolished slavery, the 14th established citizenship and equal protection, and the 15th protected voting rights for Black men. Therefore, the correct choice is passing amendments to the Constitution. The Emancipation Proclamation was issued during the war, not after it.

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