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.
实验室里形成了F,需要特定条件 —— 可以据此研究自然界F形成的条件
削弱
一直在谈fullerenes形成的过程,跟Shungite 无关
D 自然界F形成之前的晶体结构是未知的;增加了新的未知条件,即现有条件不一定推出结论
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