Prior to the effective date of retirement, but not thereafter, a member may elect to receive his or her pension as a straight life pension payable throughout his or her life, or he or she may elect to receive the actuarial equivalent, at that time, of his or her straight life pension in a reduced pension payable throughout his or her life, and nominate a beneficiary, in accordance with Option A or B, as follows:
(a) Option A - Survivor Pension. Upon the death of a retirant, his or her reduced pension shall be continued throughout the life of and paid to a person, having an insurable interest in the retirant's life, as he or she nominated by written designation duly executed and filed with the Board of Trustees prior to the effective date of his or her retirement.
(b) Option B - Modified Survivor Pension. Upon the death of a retirant, one-half of his or her reduced pension shall be continued throughout the life of and paid to a person, having an insurable interest in the retirant's life, as he or she nominated by written designation duly executed and filed with the Board prior to the effective date of his or her retirement.
(1974 Code § 1.221)