Which amendment provides that citizens eighteen (18) and older can vote?

The Twenty-sixth Amendment to the United States Constitution is the amendment that establishes the voting age as eighteen years. Ratified in 1971, this amendment was a significant step in expanding democratic rights, particularly during a time when many young adults were being drafted into military service but did not have the right to vote. It reflects the principle that if individuals are deemed responsible enough to serve in the military, they should also have the right to participate in the electoral process.

Understanding this amendment is crucial for recognizing the evolution of voting rights in the U.S., particularly concerning age and participation in democracy. The other amendments listed do not address the voting age; for instance, the Nineteenth Amendment pertains to women's suffrage, while the Second Amendment addresses the right to bear arms, and the Twenty-fourth Amendment prohibits the use of poll taxes in federal elections, which relates to voting access but not specifically to age.