Final answer:
The cost of internal product/process testing would be categorized as Appraisal cost. So, the option is D.
Step-by-step explanation:
Internal product/process testing costs are included in the category of appraisal costs, along with other costs associated with assessing and examining items to make sure they adhere to quality standards prior to customer delivery.
Appraisal costs are associated with the evaluation and inspection of products and services to ensure they meet specified quality standards. These costs occur before products are delivered to customers and are therefore distinct from external failure costs, which are costs associated with defects found by customers. Internal product testing is a form of quality control aimed at catching potential issues before products leave the company, thereby reducing the incidence of external failures and ensuring customer satisfaction.
Therefore, D. Appraisal cost is the correct option.