The creation of life requires a set of chemical elements for making the components of cells. Life Earth uses about 25 of the 92

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问题 The creation of life requires a set of chemical elements for making the components of cells. Life Earth uses about 25 of the 92 naturally occurring chemical elements, although just 4 of these element oxygen, carbon, hydrogen, and nitrogen—make up about 96 percent of the mass of living organis Thus, a first requirement for life might be the presence of most or all of the elements used by life.
The phrase "these elements" refers to ________.

选项 A、25 of the 92 naturally occurring chemical elements
B、the 92 naturally occurring chemical elements
C、the mass of living organisms
D、oxygen, carbon, hydrogen, and nitrogen

答案A

解析 上文第2句中状语从句出现了these elements,其所指应往前找。前面提到地球上的生命仅用到了 25 of the 92 naturally occurring chemical elements,而although引导的从句进一步指出,在这需要用到的25种元素中,仅4种便可组成地球上96%的生命。因此,these elements应指代上文的25 of the 92 naturally occurring chemical elements有干扰性的是B项,但从第3句中的most or all of the elements used by life也可确认,这里指的是地球上的生命需要用到的25种元素,而不是92种元素,故A项更贴切。
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