Detailed Explanation:
The correct answer is D. Internal failure.
A nonconforming product discovered during manufacturing is an internal failure cost because the defect is found before the product reaches the customer.
Internal failure costs include costs associated with defects detected within the organization, such as:
These costs arise because the process failed to produce conforming output, but the issue was identified internally before shipment or customer use.
Why the other options are incorrect:
A. Prevention
Prevention costs are costs incurred to avoid defects from occurring, such as training, process design, and quality planning.
B. Appraisal
Appraisal costs are costs of evaluating products or processes, such as inspection, testing, and audits.
C. External failure
External failure costs occur when defects are found after the product reaches the customer, such as warranty claims, returns, and complaints.
Quality Management Excellence reference basis:
This answer is consistent with Quality Management Excellence principles of:
distinguishing prevention, appraisal, and failure costs,
identifying where in the process the defect is discovered,
and using that distinction for accurate cost-of-quality analysis.
======================================================================