Which of the following functions does a Registered Retirement Income Fund (RRIF) NOT provide?

A Registered Retirement Income Fund (RRIF) is specifically designed to provide a means for individuals to convert their retirement savings into a stream of income during retirement. While RRIFs do mandate a minimum withdrawal amount based on the account holder’s age, they do not enforce a maximum withdrawal limit. This means that the account holder has the flexibility to withdraw as much as they need beyond the minimum requirement.

The idea is to offer retirees the ability to manage their funds according to their personal financial needs throughout retirement. Therefore, option B, which mentions "mandatory maximum withdrawals," does not align with the nature of RRIFs since there are no imposed maximums on withdrawals.

The other options are indeed true functions of a RRIF. Flexibility for unrestricted withdrawals reflects the ability to take out more than the required minimum. Income deferral through minimized withdrawals refers to the strategy of minimizing the amount withdrawn (but not below the minimum) to allow remaining funds to continue to grow tax-deferred. Lastly, the statement regarding no required withdrawals until a certain age refers to the stipulation that individuals can choose not to make any withdrawals until they reach a specific age, which is currently at 71 in Canada, before the mandatory minimum withdrawals kick in.