Final answer:
The nurse's priority in caring for a client who had abdominal surgery 24 hours ago is to assist with deep breathing and coughing to reduce the risk of postoperative pneumonia.
Step-by-step explanation:
The nurse's priority in caring for a client who had abdominal surgery 24 hours ago is to assist with deep breathing and coughing. This is because deep breathing and coughing exercises help to prevent postoperative pneumonia, a common complication after surgery. By assisting the client with deep breathing and coughing, the nurse can help to maintain clear airways and promote lung expansion, reducing the risk of pneumonia.