(5) QJSA. At each age, the most valuable QSUPP commencing at that age must be payable in conjunction with the QJSA commencing at that age. In addition, the plan must provide that, in the case of a social security supplement payable in conjunction with a QJSA, the social security supplement will be paid after the employee's death on the same terms as the QJSA, but in no event for a period longer than the period for which the social security supplement would have been paid to the employee had the employee not died. For example, if the QJSA is in the form of a joint annuity with a 50-percent survivor's benefit, the social security supplement must provide a 50-percent survivor's benefit. When section 417(c) requires the determination of a QJSA for purposes of determining a qualified pre-retirement survivor's annuity as defined in section 417(c) (QPSA), the social security supplement payable in conjunction with that QJSA must be paid in conjunction with the QPSA.