In Accounting for Compensated Absences, the Difference Between Vested Rights

In accounting for compensated absences, the difference between vested rights and accumulated rights is that:

A) vested rights are normally for a longer period of employment than are accumu?lated rights.
B) vested rights are not contingent upon an employee's future service.
C) vested rights are a legal and binding obligation on the company, whereas accumulated rights expire at the end of the accounting period in which they arose.
D) vested rights carry a stipulated dollar amount that is owed to the employee; accumulated rights do not represent monetary compensation.