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': 'Air embolism in neural surgery maximum in which position: \nSelect and explain. \nA. Sitting, B. Supine, C. Trendelenburg, D. Left lateral', 'role': 'user'}, {'content': "Answer: A \nExplanation: Ans is 'a' i.e. Sitting", 'role': 'assistant'}]