There are numerous conditions that the people who apply for US citizenship should fulfill. In order to become a naturalized citizen of the US, one of the basic conditions is that the applicant has 18 years of age at the date of application for the naturalized citizenship, the Form N-400. The reason as to why this is required is that the person who applies is an adult, not minor, so has the mental capacity to decide for himself/herself, and is it of his/hers best interest.
In order for a nation to exist, the statement that must be TRUE is the country must be free to exercise sovereignty in handling its own affairs. The correct answer is D.
