. A nurse is caring for a postoperative client. The nurse should base the client's pain management interventions primarily on which methods of determining the intensity of the client's pain?

A. The patient's chart may provide historical information but does not reflect the current pain intensity the client is experiencing. B. Visual observation for nonverbal signs of pain can be useful, especially for nonverbal patients, but self-reporting is the most accurate measure of pain intensity. C. The client's self-report of pain severity is the gold standard for assessing pain intensity, as it reflects the individual’s personal experience of pain. D. While the nature and invasiveness of the surgical procedure can provide context for expected pain levels, they do not replace the importance of the client's self-report in managing pain effectively.