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?
Confirming that the shungite genuinely contained fullerenes took careful experimentation.
Some fullerenes have also been found on the remains of a small meteorite that collided with a spacecraft.
The mineral shungite itself contains large amounts of carbon, from which the fullerenes apparently formed.
The naturally occurring fullerenes are arranged in a previously unknown crystalline structure.
Shungite itself is formed only under distinctive conditions.
A,F存在于S是题干给出的信息,不可质疑。
B,some F也存在在外太空,some不能否认在地球上能找到天然的F物质这一条件,因此对主要逻辑不能产生削弱作用,劣于D
C,S包含C,C组成F。推测地壳,与C无关。
D,自然形成的F包含之前未知晓的晶体结构,说明实验室生成的F与自然界的F不一样。【类比削弱】
E,S特定条件才生成。加强。
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