A client is complaining of abdominal pain and feeling hot about 24 hours after an appendectomy. The nurse determines the client's temperature is 102°F. The nurse suspects peritonitis as a possible complication based on the results of her assessment. Which of the following symptoms would support the development of this complication?

A. Decreased body temperature: Peritonitis typically causes fever (elevated temperature) due to infection/inflammation, not a decreased temperature. B. Increased bowel sounds: Peritonitis usually leads to hypoactive or absent bowel sounds because inflammation causes intestinal ileus, not increased sounds. C. Rigidity of the abdomen upon palpation: Rigid, board-like abdominal muscles (guarding/rigidity) with rebound tenderness are classic signs of peritoneal irritation/inflammation. D. Decreased pain intensity with palpation: Pain typically increases with palpation and rebound in peritonitis; decreased pain with palpation would not support peritonitis.