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A girl may pass easily through the first grades. While boys of her age bring home low marks, the girl may get easily good grades. Girls seem to have "better brains" in school. Why do so few girls become scientists? Why is the most important thinking in adult (成人) world done by men?

According to (根据) scientists, the answer is aggression (敌对行为). Boys usually refuse to accept other people's conclusion (结论). They insist on solving problems by themselves. While little girls are getting high marks in school for remembering what the teacher has told them, little boys are learning to think in their own ways. Boys are usually the ones who get high pay and the powerful job because they are to be aggressive at an early age.