(a) Option A -- Contingent joint and survivor annuity. -- A life annuity payable during the joint lifetime of the member and his or her beneficiary who must be a natural person with an insurable interest in the member's life. On the death of the member, the benefit shall continue as a life annuity to the beneficiary in an amount equal to fifty percent, sixty-six and two-thirds percent, seventy-five percent or one hundred percent of the amount paid while both were living, as elected by the member. If the beneficiary dies first, the monthly amount of benefits may not be reduced, but shall be paid at the amount that was in effect before the death of the beneficiary. If the retiring member is married, the spouse shall sign a waiver of benefit rights if the beneficiary is to be other than the spouse.
(b) Option B -- Ten years certain and life annuity. -- A life annuity payable during the member's lifetime but in any event for a minimum of ten years. If the member dies before the expiration of ten years, the remaining payments shall be made to a designated beneficiary, if any, or otherwise to the member's estate.