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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.


为什么是D呢,从哪里进行weaken的?

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要weaken就证明discovery发现的fullerenes 不具有代表性或是不适合做a test case

D说明了其的不一样 不能起represent的作用

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出不多吧,就是C的排列结构有不同的形式,所以不具有代表性

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请问这道题为什么不能选C呢?自然形成的shungite本身就含有大量碳,因此与实验室中合成的 fullereness形成条件不同,因此test case不具代表性——请问这个推法错在哪里哦?

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