This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Surgery
[{'content': 'Fluid levels are not visible in \nSelect and explain. \nA. Meconeum ileus, B. Intussusception, C. Colon pouch, D. Duodenal obstruction', 'role': 'user'}, {'content': 'Answer: A \nExplanation: In meconium ileus meconium is so thick that it is unable to form air-fluid level despite complete small intestinal obstruction (Note the multiple air-fluid level is a feature of mechanical small bowel obstruction & paralytic ileus).', 'role': 'assistant'}]