A nurse in an acute mental health care facility is prioritizing care for multiple clients. Which of the following clients should the nurse see first?

A. A client upset about a change in routine does not present an immediate threat to their health. B. Assistance with ADLs is important but not urgent compared to a possible adverse drug reaction. C. A sore throat in a client taking clozapine may indicate agranulocytosis, a potentially life-threatening condition that requires immediate evaluation. D. Mocking others is disruptive but not a priority over a potential medical emergency.