Final answer:
A work-in-process inventory file consists of cost sheets that detail production expenses for unfinished goods, including labor, materials, and overhead.
Step-by-step explanation:
A work-in-process inventory file is the collection of cost sheets. These cost sheets contain detailed information about the expenses associated with the production of goods that are not yet completed, including direct labor, direct materials, and allocated overhead. This file is essential for a company to track production costs, evaluate efficiency, and determine the cost of goods sold once the items are completed.