A nurse is teaching a client who had a total knee arthroplasty about self-administering morphine via a patient-controlled analgesia (PCA) infusion device. Which of the following client statements indicates an understanding of the teaching?

Rationale: A. The client should report inadequate pain relief to the nurse, as PCA therapy may need adjustment. This shows appropriate understanding of PCA use. B. PCA should be used as prescribed to maintain consistent pain control, not delayed until pain is severe. C. PCA pumps have lockout intervals to prevent overdosing. Clients do not need to fear self-administering doses when in pain. D. Only the client should push the PCA button. Allowing others to administer doses increases the risk of oversedation and respiratory depression.