Final answer:
Yes, the ending balance in Work-in-Process Control does represent the total costs of all unfinished jobs. It includes materials, labor, and overhead for products that are still in the production process until they are completed.
Step-by-step explanation:
The statement that the ending balance in Work-in-Process Control represents the total costs of all jobs that have NOT yet been completed is true. Work-in-Process Control is an account used in manufacturing accounting where the costs of unfinished products are accumulated. These costs include materials, labor, and overhead assigned to a product that is still in the production process. Once the job is completed, the costs are then transferred to Finished Goods Control. Until that point, the ending balance in Work-in-Process Control reflects the accumulation of these ongoing production costs.