Your best friend’s brother is rushed to the emergency room exhibiting the following symptoms. Severe pain in the middle of the abdomen between the xiphoid process and his naval. While waiting to see the doctor, his severe pain is now moving to the lower right abdominal quadrant of the abdomen and he has rebound tenderness on examination meaning it hurts when palpating the RLQ but is worse when you let go, this is known as "rebound tenderness." He has a fever and an elevated WBC with neutrophils predominant. Which digestive organ do you suspect is causing the problem? WHY?