单选题
Which of the following is the smallest in size?
A.Viruses.
B.New filters.
C.Living cells.
D.Chemical molecules.
推理题。题干意为“以下几个选项中,哪个是尺寸最小的?”。根据文章倒数第二段最后一句“…larger than the largest chemical molecules and smaller than the smallest living things.”可知,通过三者的比较,应该是chemical molecules最小。故D为正确答案。
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1
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Good Value Britain
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With Scotland Travelpass,you can__________.
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2
One use ofthe London Pass is to __________.
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