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

The 26th Amendment is the correct answer because it specifically addresses the voting rights of citizens who are eighteen years of age and older. Ratified in 1971, this amendment was a significant change in U.S. legislation, ensuring that young adults could participate in elections, reflecting the belief that those who are old enough to serve in the military should also have the right to vote.

In contrast, the other amendments listed focus on different aspects of voting rights. The 15th Amendment, ratified in 1870, prohibits the denial of voting rights based on race, color, or prior servitude. The 19th Amendment, ratified in 1920, grants women the right to vote, expanding suffrage across gender. Lastly, the 24th Amendment, ratified in 1964, prohibits the use of poll taxes in federal elections, ensuring that financial barriers do not restrict access to voting. Each of these amendments contributes to the broader context of voting rights in the United States but does not address the specific age requirement for voting as the 26th Amendment does.