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Although fullerenes--spherical molecules made entirely of carbon--were first found in the laboratory, they have since been found in nature, formed in fissures of the rare mineral shungite.  Since laboratory synthesis of fullerenes requires distinctive conditions of temperature and pressure, this discovery should give geologists a test case for evaluating hypotheses about the state of the Earth's crust at the time these naturally occurring fullerenes were formed.

 

 

Which of the following, if true, most seriously undermines the argument?

 

 

(A) Confirming that the shungite genuinely contained fullerenes took careful experimentation.

(B) Some fullerenes have also been found on the remains of a small meteorite that collided with a spacecraft.

(C) The mineral shungite itself contains large amounts of carbon, from which the fullerenes apparently formed.

(D) The naturally occurring fullerenes are arranged in a previously unknown crystalline structure.

(E) Shungite itself is formed only under distinctive conditions.

第一题就不明白,为什么正确答案是D呢?请NN帮忙解答一下。

谢谢!!!

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想了一下,大概是这样的吧?

fullerenes先在实验室里发现,然后再是自然界中发现。如果后来自然界中的和实验室里的结构不同,则试

图从试验环境中推出的结论应该是没有意义的,削弱

TOP

thanks !!!!!!!!!!!!

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