Which amendment lowered the voting age to 18?

The Twenty-sixth Amendment is the amendment that lowered the voting age to 18. Ratified in 1971, this amendment was largely influenced by the social and political climate of the time, particularly the Vietnam War, where many young Americans who were eighteen years old were being drafted to fight, yet were not allowed to vote. The amendment ensures that citizens who are 18 years of age or older cannot be denied the right to vote based on their age, thereby reflecting a significant change in law aimed at empowering younger citizens and ensuring their voices are heard in the democratic process.

In contrast, the Fifteenth Amendment addresses voting rights regardless of race but does not specifically set an age limit. The Nineteenth Amendment granted women the right to vote and is not related to age. The Twenty-fourth Amendment prohibits poll taxes in federal elections but also does not concern the voting age. Thus, the Twenty-sixth Amendment is uniquely applicable to the age of voters, making it the correct answer.