The nurse is providing postoperative care for a client recovering from abdominal surgery. The client is receiving morphine through a client-controlled analgesia pump. Which finding would indicate that the client is obtaining adequate pain relief ？（）
A．Awakening several times during the night to redose.
B．Respiratory rate of 10 breaths/minute.
C．Pain rating of 2 or 3 on a scale of 0 to 10.
D．Complaint of itching as an adverse effect of the analgesia.