Section 43(2A)(d) in Tamil Nadu Pension Rules, 1978
(d)A Government servant who entered-service prior to, 1st October , 1979 may opt for pension as per the provision in clause (a) above and for the Death-cum-Retirement Gratuity as per die provision in clause (c) of sub-rule (1) of rule 45. The option should cover both pension and Death-cum-Retirement Gratuity and not any one. The option shall be exercised one year before the date of retirement and if once exercised shall be final.