Which of the following accurately describes a 403(b) plan?

a. A 403(b) plan is a noncontributory qualified profit sharing plan

b. Because of catch-up provisions, the investment risk of the assets within a 403(b) plan is borne equally by the plan sponsor not the participant

c. A participants benefits within a 403(b) plan will generally vest according to a 3 to 7 year graduated vesting schedule; however, a 5-year cliff vesting schedule may be used

d. 403(b) plan assets can be invested indirectly in stocks and bonds through annuities or mutual funds