This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Small intestine, Subject name: Surgery
[{'content': 'Causes of non-healing of enterocutaneous fistula are all except: \nSelect and explain. \nA. Epithelialization of track, B. Radiation enteritis, C. Acute inflammatory disease, D. Track length >3 cm', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Factors Preventing Spontaneous Fistula Closure High output (>500 mL/day) Severe disruption of intestinal continuity (> 50% of bowel circumference) Active inflammatory bowel disease of bowel segment Cancer Radiation enteritis Distal obstruction Undrained abscess cavity Foreign body in the fistula tract Fistula tract <2.5 cm long Epithelialization of fistula tract', 'role': 'assistant'}]