Please help due today! Which option best explains why this statement describes a civic duty and nota civic responsibility?

Every male U. S. citizen over the age of 18 must sign up with the Selective Service. If a war breaks out, these men could be required to serve in the military.

A. Only citizens over the age of 18 are required to sign up.

B. The rule does not apply equally to male and female citizens.

C. The rule deals with issues of war and national safety.

D. Citizens do not have a choice about signing up.