A nurse is collecting data from a client who has substance use disorder and reports recently taking opioids. Which of the following findings should the nurse identify as a manifestation of opioid intoxication?

d. Pinpoint pupils. Explanation: Opioid intoxication is characterized by various signs and symptoms, including central nervous system depression. One common manifestation of opioid intoxication is pinpoint pupils (miosis), which is caused by the effect of opioids on the pupillary constrictor muscles. The pupils become constricted and appear as small dots, hence the term "pinpoint." The other options are not typical manifestations of opioid intoxication. Tachycardia (rapid heart rate) is more commonly associated with stimulant use rather than opioids. Mental alertness is typically reduced in cases of opioid intoxication, as opioids cause sedation and CNS depression. Hyperreflexia (exaggerated reflexes) is not a typical finding in opioid intoxication; instead, it may occur in withdrawal from certain substances such as alcohol or benzodiazepines.