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: Pediatrics
[{'content': 'Most common cause of lower respiratory tract infection in 3 year old child is \nSelect and explain. \nA. Klebsella, B. H-influenza, C. Streptococcal pneumonia, D. Staphe aureus', 'role': 'user'}, {'content': "Answer: C \nExplanation: Ans. is 'c' i.e., Streptococcal pneumonia", 'role': 'assistant'}]