Imagine you are Alice, stepping through the looking glass. Suddenly everything is re versed. Doorknobs are on the wrong side of doors. The gearshift in your car is in the wrong place. Twenty-five million Americans wake up every day in just such an awkward situation. They are the one in ten of us who are left-handed and must face the world designed for the right-handed majority. Why we are left-or-right-handed remains one of the great unsolved mysteries of science. We know that nearly two out of three lefties are male and that left-handedness runs in families. According to one study, almost half the offspring of two left-handed parents will be lefthanded. The Scots-Irish family Kerr (from the Gaelic word for "left") produced so many left-handers that in 1470 the family built its castle’s spiral stairways with a reverse twist to favor left-handed swordsmen. On the other hand, heredity alone cannot explain leffies. At least 84 percent of them are born of two right-handed parents. And in 12 percent of genetically identical twins, one will be right-handed, the other left. Perhaps the greatest puzzle of all is not why some people are left-handed, but rather why so few are. So, scientists are trying to discover the truth of the matter, and they are beginning to gain insight into many ways left-handed differ from right-handed by considering how their brains work.According to the passage, which of the following is NOT true（） A．Almost half of the children of two left-handed parents will be left-handed B．At least 84 percent of left-handers are born of two right-handed parents C．One in ten of Americans are left-handed D．In the majority of genetically identical twins, one will be right handed, the other left
Imagine you are Alice, stepping through the looking glass. Suddenly everything is re versed. Doorknobs are on the wrong side of doors. The gearshift in your car is in the wrong place. Twenty-five million Americans wake up every day in just such an awkward situation. They are the one in ten of us who are left-handed and must face the world designed for the right-handed majority. Why we are left-or-right-handed remains one of the great unsolved mysteries of science. We know that nearly two out of three lefties are male and that left-handedness runs in families. According to one study, almost half the offspring of two left-handed parents will be lefthanded. The Scots-Irish family Kerr (from the Gaelic word for "left") produced so many left-handers that in 1470 the family built its castle’s spiral stairways with a reverse twist to favor left-handed swordsmen. On the other hand, heredity alone cannot explain leffies. At least 84 percent of them are born of two right-handed parents. And in 12 percent of genetically identical twins, one will be right-handed, the other left. Perhaps the greatest puzzle of all is not why some people are left-handed, but rather why so few are. So, scientists are trying to discover the truth of the matter, and they are beginning to gain insight into many ways left-handed differ from right-handed by considering how their brains work.According to the passage, which of the following is NOT true（） A．Almost half of the children of two left-handed parents will be left-handed B．At least 84 percent of left-handers are born of two right-handed parents C．One in ten of Americans are left-handed D．In the majority of genetically identical twins, one will be right handed, the other left
题目解答
答案
D
解析
文章讨论了左撇子和右撇子的分布情况，以及左撇子的一些特点和遗传因素。问题要求找出文章中不正确的陈述。
步骤 2：分析选项
A. 几乎一半的两个左撇子父母的孩子会是左撇子。文章中提到，根据一项研究，几乎一半的两个左撇子父母的孩子会是左撇子，因此这个选项是正确的。
B. 至少84%的左撇子是由两个右撇子父母生的。文章中提到，至少84%的左撇子是由两个右撇子父母生的，因此这个选项也是正确的。
C. 美国每十个人中就有一个是左撇子。文章中提到，美国每十个人中就有一个是左撇子，因此这个选项也是正确的。
D. 在大多数基因相同的双胞胎中，一个会是右撇子，另一个会是左撇子。文章中提到，在12%的基因相同的双胞胎中，一个会是右撇子，另一个会是左撇子。因此，这个选项是不正确的，因为12%并不意味着“大多数”。
步骤 3：得出结论
根据文章内容，选项D是不正确的，因为12%并不意味着“大多数”。