(a) The election of the options provided in this Part shall be made on blanks prepared by the Comptroller for that purpose. Any such election may be made at any time before the first payment on account of any benefit becomes normally due. In the case of retirement on account of disability, the election of either the five-year certain option or the ten-year option may be made within 30 days after mailing by the Comptroller of notification of approval of retirement on account of disability. An election of an option may be withdrawn or a new option may be chosen at any time before the first payment on account of any benefit becomes normally due or within 30 days of the mailing of notification by the Comptroller of approval of retirement on account of disability.

(b) An election of option shall be ineffective until it is filed in the office of the Comptroller.

(c) The Comptroller, for reasonable cause, may extend the time for the election of an option for a period or periods which shall expire not later than 60 days immediately after the effective date of the member's retirement.