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': 'Anaesthesia used in microlaryngoscopy is – \nSelect and explain. \nA. Pollarad tube of 10 mm diameter with heavy sedation, B. Pollarad tube of 15 mm diameter with topical xylocaine, C. Pollarad tube with infiltration block, D. Heavy sedation on and endotracheal intubation', 'role': 'user'}, {'content': "Answer: C \nExplanation: Actually, no option is absolutely correct. However, option 'c' is the best one.\nOption a & b can be excluded as In microlaryngoscopy tube of smaller diameter (4-6 mm) are used.\nOption 'd' can be excluded as microlaryngoscopy is done either in local or general anaesthesia (not in sedation).\nNow we are left with option 'c'. Pollard tube was the earliest tube which was used for Microlaryngoscopy. However, newer and better tubes are now available.", 'role': 'assistant'}]