Answer:
C. Outside the school or workday.
Explanation:
It really depends on the situation and time.
A./Comunity service is usually volunteer work, so it's not for minimum wage
B./You don't usually do community service DURING school hours- unless you don't go to school- or it's a school "assignment"
D./The majority of Community service is to help your community, though a good chunk of it is to help the elderly- it's not entirely for them.
As it makes the most logical choice... your final answer
C.