Please help me solve this general accounting question using the right accounting principles.

A.Q. Manufacturing uses a process-costing system. Products are manufactured in a series of three departments. The following data relate to Department Three for the month of April: Item Units/Amount Beginning work-in-process (80% complete) | 16,500 units Goods started in production 78, 000 units Ending work-in-process (70% complete) 10,800 units The beginning work-in-process was valued at $89, 200, consisting of $31,500 of transferred-in costs, $39,800 of materials costs, and $17,900 of conversion costs. Materials are added at the beginning of the process; conversion costs are added evenly throughout the process. Costs added to production during April were: Cost Category Amount Transferred-in | $27, 200 Materials used | $112,500 Conversion costs| $68, 400 Assuming the company uses the FIFO method of inventory valuation, what amount of materials cost is included in A.Q@. Manufacturing' s ending work-in-process inventory? A. $10, 506 B. $16, 450 C. $13, 300 D. $15, 552