Titan Corporation offers its employees a defined benefit plan with graded vesting. The vesting percentage grows by 15 percentage points a year each year after years one through five, the worker becomes fully vested in year six. Does this meet ERISA'S requirements? O A. Yes B. No, as a defined benefit graded vesting plan must occur over seven years. OC. No, as the vesting percentage must rise by 20 percentage points each year until fully vested. OD. NO, as the largest percentage increase in year 6 qualifies as illegal backloading