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': '90% of brain growth is achieved by the - \nSelect and explain. \nA. 2nd year, B. 3rd year, C. 5th year, D. 15th year', 'role': 'user'}, {'content': "Answer: A \nExplanation: Ans. is 'a' i.e., 2nd year o The brain enlarges rapidly during the latter months of fetal life and early months of postnatal life. o At bih, the head size is about 65 to 70 percent of the expected head size in adults. o It reaches 90 percent of the adult head size by the age of 2 years.", 'role': 'assistant'}]