Answer: a. raw materials, work in process, finished goods
Raw materials are items that need to go through production (become works in progress) to become finished goods, all of which are recorded.
Manufacturing costs could be either direct materials, direct labor, or factory overhead costs. The direct costs can be charged to a particular cost object (say a product for example), whereas the factory overhead costs are mainly about indirectly assigned items, for example, factory utility costs, and the salary of the factory supervisor.