There shall be a provision as follows:
Change of beneficiary: Unless the insured makes an irrevocable designation of beneficiary, the right to change of beneficiary is reserved to the insured and the consent of the beneficiary or beneficiaries shall not be requisite to surrender or assignment of this policy or to any change of beneficiary or beneficiaries, or to any other changes in this policy.
(The first clause of this provision, relating to the irrevocable designation of beneficiary, may be omitted at the insurer's option.)