The following is an account for a production department, showing its costs for one month:

Work in Process Inventory
Beginning Balance 5,400 Completed and transferred out 49,410
Direct materials 21,600
Direct labor 16,200
Overhead 10,800
Ending Balance 4,590

Assume that materials are added at the beginning of the production process and that direct labor and overhead are applied uniformly. If the started and completed units cost $41,850, what was the cost of completing the units in the beginning Work in Process inventory?

a. $16,950.
b. $37,260.
c. $10,760.
d. $3,760.
e. $60,400.