Which Statement About On-Campus Employment Is True

Which statement about on-campus employment is true?

A) Students with on-campus jobs tend to earn higher wages than students working off-campus.
B) On-campus jobs are available only to students who are enrolled in a federal work-study program.
C) On-campus supervisors are generally less flexible than off-campus employers in helping you balance your study demands and work schedule.
D) Students with on-campus jobs have opportunities to develop relationships with influential people who might later write a reference letter for them.