Final answer:
All male citizens between 18 and 25 must register for a potential military draft in the United States.
Step-by-step explanation:
All male citizens between 18 and 25 must register for a potential military draft in the United States. This requirement is established by the Selective Service System, which is responsible for maintaining a database of potential draftees in case of a national emergency or war that requires a draft. It is important to note that registration for the military draft does not necessarily mean individuals will be drafted into the military.
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