The vegetative forms of most bacteria are killed by drying in air, although the different species exhibit pronounced differences

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问题     The vegetative forms of most bacteria are killed by drying in air, although the different species exhibit pronounced differences in their resistance. The tubercle bacillus is one of the more resistant, and vibrio bacterium is one of the more sensitive to drying. In general, the encapsulated organisms are more resistant than the non-encapsulated forms. Spores are quite resistant to drying; the spores of the anthrax bacillus, for example, will germinate alter remaining in a dry condition for years or more. The resistance of the pathogenic forms causing disease of the upper respiratory tract is of particular interest in connection with airborne infection, for the length of time that a droplet remains infective is a result, primarily, of the resistance of the particular microorganism to drying.
It may be inferred from the passage that______.

选项 A、bacteria can be most easily killed by removal of moisture
B、drying out a house will eliminate the risk of airborne infection
C、hot-air heating is better than steam heating because steam heating uses water
D、none of the above

答案C

解析 本题中,A项不正确,文章只是说明细菌在干燥环境下不易存活,但并没有经过对比表示烘干是消灭细菌的最简便的方法;B项“干燥房屋能完全防治传染”说得过于绝对,因为有些细菌在干燥空气下仍有顽强的生命力;C项说法合情合理,热空气加热比蒸汽加热要好,因为后者水分含量高,易形成潮湿环境。从生物学和物理学的角度来看,这也是一个常识。因此正确答案为C。
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