有关性连锁基因的近婚系数，下列何者错误？（）
A.计算性连锁基因的近婚系数时，男女孩都应计算
B.男孩的X染色体均来自母亲，所以追查基因传递步骤时，不计算男性
C.姨表兄妹结婚，其女儿的性连锁基因近婚系数为3/16
D.舅表兄妹结婚，其女儿的性连锁基因近婚系数为1/8
E.堂兄妹结婚和姑表兄妹结婚，其女儿的性连锁基因近婚系数均为0
参考答案：A
完形填空 先通读下面的短文，掌握其大意，然后在所给选项中，选出最佳选项。 At the beginning of this century, medical scientists made an interesting discovery: we are built not just of flesh (肌肉) and blood but also of time. They were able to show that we all have a ‘body clock’ 1 us, which controls the 2 and fall of our body energies. It can 3 us different from one day to the next. The idea of a ‘body clock’ should not be too 4 because the lives of most living things are controlled by the 24-hour night-and-day cycle (循环). We feel 5 and fall asleep at night. We become 6 and energetic during the day. Most people will have a bad feeling if the 24-hour cycle is 7 . For example, people who are not used to working at night can find that lack (缺少) of sleep causes them to 8 badly at work. 9 the daily cycle of sleeping and waking, we also have other cycle which lasts longer than one day. Most of us would 10 that we feel good on some days and not so good on others; sometimes our ideas seem to be so active and at other times, they are not.
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