A 51-year old man is brought to the emergency room having severe abdominal pain

A 51-year old man is brought to the emergency room having severe abdominal pain. The pain is radiating to his back and the patient has also had many episodes of vomiting already. The patient is an alcoholic, drinking daily. Physical examination notices him lying down in the fetal position and appearing to be ill and febrile. There is also an area of bluish periumbilical discoloration on the skin of his abdomen. However, there is no flank discoloration. There is also reduced bowel sounds and he is having severe mid epigastric soreness upon palpitation. The rectal exam is normal.
Which of the following diagnosis would be the right fit?
A- Appendicitis
B- Pyelonephritis
C- Necrotizing pancreatitis
D- Acute cholecystitis