" My very educated mother just served us nine pizzas. " Many American school children are taught this sentence to help them reme

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问题     " My very educated mother just served us nine pizzas. " Many American school children are taught this sentence to help them remember the order of the planets of the solar system. Soon though, this may change because, on July 29th, a team of astronomers announced the discovery of a very distant celestial body larger than Pluto. The researchers claim that the new body—which they are informally calling Xena—should be classified as a planet.
    The new body—temporarily named 2003 UB313—orbits the Sun once every 560 years. It is currently over 14 billion kilometres away, about three times farther out than Pluto, making it the most distant object ever discovered in the solar system. The researchers think it is part of the Kuiper belt, a ring of rocky objects that extends beyond Neptune.
    Mike Brown of the California Institute of Technology, Chad Trujillo of the Gemini Observatory and David Rabino witz of Yale University discovered the object in data recorded at the Palomar Observatory in San Diego in October 2003, but its motion did not become apparent until they reanalysed the data in January 2005.
    The question of whether or not the new body should be considered a planet has rekindled the debate over what exactly counts as a planet. A handful of objects of similar size to, but smaller than, Pluto have been discovered in the Kuiper belt over the past few years. These have not been considered planets, mainly because they were smaller than Pluto. But 2003 UB313 is larger than Pluto. If Pluto is a planet, shouldn’t it be as well?
    The case is not so clear cut. Many astronomers argue that Pluto should not be considered a planet. It is more like a large asteroid, they hold. Meanwhile, Dr Brown asserts that as Pluto has historically been considered a planet, anything larger should also be considered one.
    Ultimately,the International Astronomical Union, a group of professional astronomers, will end this existential anxiety. Dr Brown expects the process to take months, and the team is not allowed to reveal its suggested name until then. Since most Greek and Roman names have already been used, he and his colleagues have previously drawn upon Native American and Inuit mythology for names. He will only hint that the new name comes from a different tradition altogether.
    Time will tell whether mother will be serving " nine polished xylophones", " nine pizzas" or just "noodles".  
The standards of planet are open to question because______.

选项 A、Pluto is now one of the nine planets
B、Pluto is a historical mistake
C、objects of size similar to Pluto are not recognized
D、2003 UB313 is larger than Pluto

答案C

解析 细节题。根据题文同序规律游览第四段内容,第四段首句出现了the question,正是对有关该星体是否为行星进行的说明,故确定为本题考点。该句指出:新星体是否是行星再次引发了有关什么是行星的争论。该段第二句和第三句提到:在过去几年里,发现了一些与冥王星差不多大,但稍小些的星体,人们并不认为它们是行星,主要是因为其体积比冥王星小。可见这是引起对判断行星的标准产生争议的原因,故[C]为答案。此处内容与冥王星是否为九大行星之一无关,排除[A]。这里并没有对冥王星是行星这一事实提出质疑,[B]毫无根据,故排除。本段倒数第二句提到[D]中的内容,但人们质疑的是体积比冥王星小的物体被认为不是行星,那么体积比冥王星大的就是行星吗?可见与[C]相比,[D]只是间接原因,故排除。
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