Fiona is a 79-year-old widow with three adult children; two are independent and the third, Melanie, is severely disabled and financially dependent on her. Fiona was married to Frank for 45 years until he died 3 years ago. Fiona is looking to invest $400,000 in a straight life annuity. She expects that the payments from the annuity will cover her monthly living and non-discretionary expenses. Which factor will most affect the amount of annuity payments in Fiona's situation?

A.Fiona having a severely disabled child.

B.Fiona being a widow.

C.The general inflation rate.

D.Fiona's age.