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单选题
According to the text, incomplete combustion is more likely to occur with gasoline than with an alternative fuel because ______.
A

the combustion of gasoline releases photochemical active hydrocarbons

B

the combustion of gasoline embraces an intricate set of reactions

C

gasoline molecules have a simple molecular structure

D

gasoline is composed of small molecules

参考答案

参考解析
解析：
推断题。文章第二段提到“The combustion of larger molecules, which have multiple carbon-carbon bonds involves a more complex series of reactions. These reactions increase the probability of incomplete combustion and are more likely to release uncombusted and photochemical active hydrocarbon compounds into the atmosphere”，即这些反应会导致不完全燃烧，这里的“these reactions”指的就是a more complex series of reactions，因此B项“汽油的不完全燃烧包括一些列复杂的反应”与原文意思相符，为正确答案。
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