M-Howard Inc. has a defined benefit pension plan. On December 31 (the end of the fiscal year), the company received the PBO report from the actuary. Among the information included in the report were the following items: ending PBO, $110,000; benefits paid to retirees, $10,000; interest cost, $7,200. The discount rate applied by the actuary was 8%. What was the beginning PBO?
a. $ 90,000
b. $100,000
c. $107,200
d. $112,000