My brother-in-law worked as a full-time school teacher in San Diego for 35 years. When he completed his 35 years of service, he retired and now receives -- based on his salary and years of service -- $6,000 per month for the rest of his life. This type of employer-sponsored retirement plan is best described with which of the following phrases:

(A) Fixed compensation
(B) Defined benefit
(C) Perpetual benefit
(D) Contingent benefit
(E) Defined contribution