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: Anaesthesia
[{'content': 'Armoured enforcement of ET tube is used in – \nSelect and explain. \nA. Neurosurgery, B. Cardiac surgery, C. Liver surgery, D. Intestinal Surgery', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Armored ET tube (Spiral embedded) is used for head & neck, maxillofacial and neurosurgeries.', 'role': 'assistant'}]