When we accept the evidence of our unaided eyes and describe the Sun as a yellow star, we have summed up the most important sing

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问题      When we accept the evidence of our unaided eyes and describe the Sun as a yellow star, we have summed up the most important single fact about it--at this moment in time. It appears probable, however, that sunlight will be the color we know for only a negligibly (微不足道的) small part of the Sun’s history.
   Stars, like individuals, age and change. As we look out into space, we see around us stars at all stages of evolution. There are faint blooded dwarfs so cool that their surface temperature is a mere 4,000 degrees Fahrenheit; there are scaring ghosts blazing at 100,000 degrees Fahrenheit and almost too hot to be seen, for the great part of their radia-tion is in the invisible ultraviolet range. Obviously, the "daylight" produced by any star depends on its temperature; today (and for ages to come) our Sun is at about 10,000 de-grees Fahrenheit, and this means that most of the Sun’s light is concentrated in the yellow band of the spectrum, falling slowly in intensity toward both the longer and shorter light waves.
    That yellow "hump" will shift as the Sun evolves, and the light of the day will change accordingly. It is natural to assume that as the Sun grows older, and uses up its hydrogen fuel-which it is now doing at the spanking rate of half a billion tons a sec-ond-it will become steadily colder and redder.
What does the author say is especially important about the Sun at the present time?

选项 A、It appears yellow.
B、It always remains the same.
C、It had a short history.
D、It is too cold.

答案A

解析 本题属细节判断题。根据题目中的important about the Sun at the present time找到短文的对应处,即第一段的开头When we accept the evidence of our un-aided eyes and describe the Sun as a yellow star,we have summed up the most important single fact about it-at this moment in time.可从这句话得知,作者认为我们肉眼见到的是黄色星球——太阳这一现象在当前来讲是极为重要的。
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