A nurse on a medical-surgical unit is observing an assistive personnel (AP) provide care for a group of clients. Which of the following actions by the AP requires intervention by the nurse?

Ambulates a client who is 2 days postoperative following a total hip arthroplasty

Measures the urinary output of a client who has an indwelling urinary catheter

Evaluates the effectiveness of the client's pain medication

Performs a simple dressing change on a client's foot wound