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What is 90% of brain growth is achieved by the - and explain in detail?
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.