<prompt> Please answer with one of the option in the bracket. Write reasoning in between . Write answer in between .Q:Five days after undergoing a pancreaticoduodenectomy for pancreatic cancer, a 46-year-old woman has 2 episodes of non-bilious vomiting and mild epigastric pain. She has a patient-controlled analgesia pump. She has a history of hypertension. She has smoked one pack of cigarettes daily for 25 years. She drinks 34 beers daily. Prior to admission to the hospital, her only medications were amlodipine and hydrochlorothiazide. Her temperature is 37.8C 100F, pulse is 98min, and blood pressure is 11682 mm Hg. Pulse oximetry on room air shows an oxygen saturation of 96. Examination shows a midline surgical incision over the abdomen with minimal serous discharge and no erythema. The abdomen is soft with mild tenderness to palpation in the epigastrium. The remainder of the examination shows no abnormalities. Laboratory studies show:Hemoglobin 11.6 gdLLeukocyte count 16,000mm3SerumNa 133 mEqLK 3.4 mEqLCl- 115 mEqLGlucose 77 mgdLCreatinine 1.2 mgdLArterial blood gas on room air shows:pH 7.20pCO2 23 mm HgpO2 91 mm HgHCO3- 10 mEqLWhich of the following is the most likely cause of this patients acid-base status?? A: Adrenal insufficiency, B: Excessive alcohol intake, C: Rhabdomyolysis, D: Adverse effect of medication, E: Fistula,  <response>: This is a question about acid-base disorders in a postoperative patient. Based on the clinical vignette, the patient recently underwent pancreaticoduodenectomy surgery and now presents with vomiting, pain, and an arterial blood gas showing metabolic acidosis. The key findings are:- Recent major abdominal surgery - Vomiting and pain suggestive of postoperative complication- Metabolic acidosis on ABG The answer choices provide possible explanations for the metabolic acidosis. Based on the clinical history, the most likely cause appears to be a postoperative complication such as anastomotic leak or intra-abdominal abscess leading to septic shock. Of the choices given, E for fistula seems most plausible.E: Fistula 