This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Airway, Subject name: Anaesthesia
[{'content': 'For 30 kg adult the size of laryngeal mask airway most appropriate is:- \nSelect and explain. \nA. 3, B. 2.5, C. 4, D. 5', 'role': 'user'}, {'content': 'Answer: A \nExplanation: LMA Sizing LMA Size Patient Size 1 Neonate / Infants < 5kg 1 1/2 Infants 5-10 kg 2 Infants / Children 10-20 kg 2 1/2 Children 20-30 kg 3 Children / Small adults 30-50 kg 4 Adults 50-70 kg 5 Large adult > 70 kg The largest possible size that will fit comfoably in the oral cavity should be chosen.', 'role': 'assistant'}]