The answer is B. All I'm asking for is a detailed solution of the answer. Just need the explanation of how to get the answer.

12. The Thomas Company has two service departments and two operating departments. The following data are available for a recent period: Service DepartmentsOp. Departments Cafeteria Custodialtingtssembly Finishing Overhead cos $80,000 $60,000 $75,000 $86,500 60 25,000 360 60,000 180 90,000 Number of employees.. 30 Square feet occupied Thomas allocates service department costs by the step method in the following order: Cafeteria costs are allocated first, based on the number of employees; Custodial Department costs are allocated second, based on square feet occupied. No distinction is made between fixed and variable costs. After all allocations, total amount of overhead cost contained in the Finishing Department will be: A) $156,800 B) $151,300 C) $154,600 D) $138,450 E) None of above. 18,000