求教！GWD第四套40题

AnnieFFish

HarrisZheng 发表于 2012-10-4 20:47
讲故事最容易理解 张三有n个儿子，如果都是一个爹生的，这n个儿子肯定都长的很像，因为这n个都长得很像，所 ...

?  ！！！

AnnieFFish

想了想为什么E不对
It fails to consider whether there could have been strains of bacteria that originated on Earth and later died out

它只是说could have been，没有说是否所有地球上的细菌都die out
则
1. all bacteria that originated on Earth later died out --> 现存的都是来自Mars的细菌，因此才测不出不同的蛋白质 --> 所以不能得出来自MARS的细菌都die out了 .  可以削弱原文结论。
2. some bacteria that originated on Earth later died out --> 但是测不出不同的蛋白质 --> 可以推测来自MARS的细菌都die out了。
   支持了原文结论

因此E选项不行。