The temperature of the Sun is over 5 000 degrees Fahrenheit at the surface, but it rises to perhaps more than 16 million degrees

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问题     The temperature of the Sun is over 5 000 degrees Fahrenheit at the surface, but it rises to perhaps more than 16 million degrees at the center. The Sun is so much hotter than the Earth that matter can exist only as a gas, except at the core. In the core of the Sun, the pressures are so great against the gases that, despite the high temperature, there may be a small solid core. However, no one really knows, since the center of the Sun can never be directly observed.
    Solar astronomers do know that the Sun is divided into five layers or zones. Starting at the outside and going down into the Sun, the zones are the corona (日冕, 光环层),chromosphere (色球层),photosphere (光球层),convection zone(对流层),and finally the core. The first three zones are regarded as the Sun’s atmosphere. But since the Sun has no solid surface, it is hard to tell where the atmosphere ends and the main body of the Sun begins.
    The Sun’s outermost layer begins about 10 000 miles above the visible surface and goes outward for millions of miles. This is the only part of the Sun that can be seen during an eclipse (日 食) such as the one in February, 1979. At any other time, the corona can be seen only when special instruments are used on cameras and telescopes to shut out the glare of the Sun’s rays.
    The corona is a brilliant, pearly white, filmy light, about as bright as the full Moon. Its beautiful rays are a sensational sight during an eclipse. The corona’s rays flash out in a brilliant fan that has wispy (纤细的) spike-like rays near the Sun’s north and south poles. The corona is thickest at the Sun’s equator.
    The corona rays are made up of gases streaming outward at tremendous speeds and reaching a temperature of more than two million degrees Fahrenheit. The rays of gas thin out as they reach the space around the planets. By the time the Sun’s corona rays reach the Earth, they are weak and invisible.
There may be a solid core at the center of the Sun______.

选项 A、because the pressures are great
B、for the temperature is not high enough
C、in spite of the great pressures
D、because of the high temperature

答案A

解析 本题是一道具体细节题。问在太阳的中心可能会有一个固体的核心,原因是什么。利用查阅式阅读法,我们可以在文章的第一段中找到相关信息。这部分指出,在太阳的核心,气体受到极强的压力以至于尽管温度很高,那里也可能有个小固体核心。因此,本题的正确答案应是A“因为那里的压力太大了”。
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