Which of the following describes appraisal costs?

	a.	They are incurred to prevent the production of products that do not conform to specifications.
	b.	They are incurred to detect which of the individual units of products do not conform to specifications.
	c.	They are incurred on defective products before they are shipped to customers.
	d.	They are incurred on defective products after they have been shipped to customers.
	e.	None of the answers.