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?
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Correct answer: D
The argument concludes that the conditions in Earth's crust where naturally occurring fullerenes were found must have been similar to the laboratory conditions under which synthetic fullerenes are created. This conclusion depends on the assumption that natural fullerenes and synthetic fullerenes are fundamentally the same. Option (D) undermines this argument by revealing that naturally occurring fullerenes are arranged in a previously unknown crystalline structure, meaning they are structurally different from laboratory-synthesized fullerenes. Since the two types of fullerenes are not the same, information about the conditions needed to create one type cannot be applied to the conditions that formed the other type.