Which amendment abolished slavery in the United States?

The 13th Amendment is the correct choice as it explicitly abolished slavery in the United States. Ratified in December 1865, this amendment states, "Neither slavery nor involuntary servitude, except as a punishment for crime whereof the party shall have been duly convicted, shall exist within the United States, or any place subject to their jurisdiction." This was a pivotal step in American history, marking a significant legal and moral shift following the Civil War.

The other amendments listed address different issues. The 12th Amendment focuses on the electoral process for the President and Vice President, the 14th Amendment grants citizenship rights and equal protection under the law, and the 15th Amendment prohibits denying the right to vote based on race. Each of these amendments plays an essential role in the framework of American constitutional law but does not directly pertain to the abolition of slavery. Thus, the 13th Amendment stands out as the one that specifically and definitively ended the institution of slavery in the country.