Which set lists the four main categories of inventory?

• A. Raw materials, work-in-process, finished goods, maintenance, repair, and operating supplies
• B. Raw materials, finished goods, WIP, MRO
• C. Raw materials, WIP, finished goods, packaging
• D. Raw materials, WIP, finished goods, service inventory

Answer: (B)

The main idea here is how inventory is typically organized in manufacturing: raw materials, work-in-process, finished goods, and maintenance, repair, and operating supplies (MRO). Raw materials are the basic inputs sourced from suppliers to be used in production. Work-in-process covers items currently in the production steps. Finished goods are those completed and ready for sale. MRO includes tools, lubricants, cleaning supplies, and other items that support production and operations but aren’t part of the final product.

This four-category framework is why the best option lists raw materials, work-in-process, finished goods, and MRO. Other options mix in items like packaging or service inventory, which aren’t regarded as one of the four main inventory categories in this standard classification.