Answer:
All of the following
Step-by-step explanation:
All of the following includes the circumstances stated below.
i) all years of the service, whether vested or non vested based on the current level of salary as the basic.
ii) only with the vested benefits, which shall be based on current salary level only.
iii) both vested or non vested salaries based on some future salaries.
With the term vested we mean, the employees which already owns some stated percentage of his retirement benefits.