Upon the death of a beneficiary who was receiving an annuity under this part due to the death of a participant, payment shall be made as follows:
(a)
Upon the death of a beneficiary under a joint and survivor option, no amount shall be payable.
(b)
Upon the death of a beneficiary who elected a single life annuity without a cash refund feature, no amount shall be payable.
(c)
Upon the death of a beneficiary who was receiving a period certain annuity, the actuarial equivalent of the remaining balance of payments shall be paid in a lump sum to the estate of the beneficiary unless the beneficiary designated a payee to receive the remaining balance of payments as provided in Section 27004.