Final answer:
The nurse should prioritize encouraging deep breathing and coughing exercises as an intervention to prevent postoperative pneumonia and atelectasis in a client with reduced mobility following surgery.
Step-by-step explanation:
The nurse should prioritize encouraging deep breathing and coughing exercises as an intervention to prevent postoperative pneumonia and atelectasis in a client with reduced mobility following surgery. After foot surgery, reduced mobility can lead to shallow breathing and decreased lung expansion, increasing the risk of pneumonia and atelectasis. Encouraging the client to take deep breaths and cough helps to prevent fluid accumulation and promote lung expansion, reducing the risk of respiratory complications.