Is there an age requirement for submitting the N-400 application?

The correct answer is that applicants must be at least 18 years old to submit the N-400 application for naturalization. This age requirement is established by U.S. immigration law, which specifies that individuals must be of legal age to apply for citizenship independently. While minors can be included in their parent's application or may have pathways to citizenship through their parents, they cannot file the N-400 on their own until they reach 18. This threshold is crucial because it signifies the age at which a person is considered an adult in the context of legal responsibilities and rights, including the right to seek citizenship.