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: Answer is 'a' i.e. Meconeum ileus In meconium ileus meconium is so thick that it is unable to form air-fluid level desptie complete small intestinal obstruction (Note the multiple air-fluid level is a feature of mechanical small bowel obstruction & paralytic ileus).", 'role': 'assistant'}]