What is one promise you make when you become a United States citizen? (65/20 version)

When you become a U.S. citizen, you take the Oath of Allegiance, in which you promise to give up loyalty to other countries, to support and defend the Constitution and laws of the United States, to obey the laws, and to serve the nation if needed — naming any of these promises is correct on this 65/20 civics question. The oath reflects the responsibilities of citizenship. It does not require giving up foreign travel or paying extra taxes, and military service is required only 'if needed' and 'if the law requires it.' Understanding the promises in the citizenship oath is part of the rights-and-responsibilities content.