A nurse is caring for an adult male client who is alert and oriented x4 on the medical-surgical unit. In regard to the pain experience, which of the following is correct?

Choice A rationale: Vital signs may change with acute pain but do not reliably validate pain, as chronic pain often occurs without significant physiologic alterations in vital signs. Choice B rationale: Chronic pain involves both physiological and psychological components, including emotional, cognitive, and behavioral factors, so it is not mostly physiological in nature. Choice C rationale: Secondary data from family may provide context but cannot replace the client’s self-report, which is the most accurate measure of pain experience. Choice D rationale: The client is the best authority on their pain, as pain is a subjective experience and self-report remains the most reliable indicator for assessment and management.