Should she stay in a RRIF or buy a life annuity?

I have a client,a single lady 75 years old,who draws the minimum payment of approx $ 726 monthly from her $100,000 RRIF.

Now here is the question. A life annuity guaranteed 10 years will pay her $766 monthly for life. As the income amounts are similar, should she stay with the RRIF or take the life annuity? The RRIF is earning about 4 % a year,but if she continues with the RRIF, she will deplete her capital and could in fact outlive it. What should she do?