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OG-25题,请教

OG的第五篇文章,是关于动物细胞在胚胎期的发展

25、 It can be inferred from the passage that the mophorgenetic determinants present in tne early embroy are

...
C  inactive until the embroy cell become irreversibly committed to their final function
...
E  present in large quntities than is necessary for the development of a single individual

看了OG的解释后,对正确选项E可以理解,但是原文中也有这么一段话:In the unfertilized egg, the substances are inactive and not distributed homogeneously.那么为什么排除C呢?OG 对C 选项的解释仅限于directly contracted by information from the passage ,对此无法理解
请帮忙解释一下,谢谢!
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答案C 的问题出在时间的修饰上。inactive until the embroy cell become irreversibly committed to their final function 。
until the embroy cell become irreversibly committed to their final function是不对的。when the egg is fertilized,the substances become active and,。。。。
不是胚胎发育到不能改变命运的地步,而是刚有胚胎就已经 active。

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