[求助]GWD3-Q5求解

solotom

  In 1994, a team of scientists led by David Mckay began studying the meteorite ALH84001, which had been discovered in Antarctica in 1984. Two years later, the McKay team announced that ALH84001, which scientists generally agree originated on Mars, contained compelling evidence that life once existed on Mars. This evidence includes the discovery of organic molecules in ALH84001, the first ever found in Martian rock. Organic molecules—complex, carbonbased compounds—form the basis for terrestrial life.  The organic molecules found in ALH84001 are polycyclic aromatic hydrocarbons, or PAH’s.  When microbes die, their organic material often decays into PAH’s.

         Skepticism about the McKay team’s claim remains, however.  For example, ALH84001 has been on earth for 13,000 years, suggesting to some scientists that its PAH’s might have resulted form terrestrial contamination. However, McKay’s team has demon stated that the concentration of PAH’s increases as one looks deeper into ALH84001, contrary to what one would expect from terrestrial contamination. The skeptic’s strongest argument, however, is that processes unrelated to organic life can easily produce all the evidence found by McKay’ s team, including PAH’s.  For example, star formation produces PAH’s.  Moreover, PAH’s frequently appear in other meteorites, and no one attributes their presence to life processes. Yet McKay’s team notes that the particular combination of PAH’s in ALH84001 is more similar to the combinations produced by decaying organisms than to those originating form nonbiological processes.

Q5: The passage asserts which of the following about the claim that ALH84001 originated on Mars?

A.      It was initially proposed by the McKay team of scientists.

B.      It is not a matter of widespread scientific dispute.

C.      It has been questioned by some skeptics of the McKay team’s work.

D.      It has been undermined by recent work on PAH’s.

E.       It is incompatible with the face that ALH84001 has been on Earth for 13,000 years.
                    B--A

 依据定位，我觉得，既然大家都普遍认为，那么肯定就不是一个争议问题，为什么标准答案选A呢？怎么也看不出来啊！请各位牛牛指导，不甚感激！

 依据定位，我觉得，既然大家都普遍认为，那么肯定就不是一个争议问题，为什么标准答案选A呢？怎么也看不出来啊！请各位牛牛指导，不甚感激！

dianecarton

不明白

[此贴子已经被作者于2008-9-11 23:13:33编辑过]

mm007_mmgmat

是啊，有没有大虾？？？

stellachan

2道一样的题??

怎么那个说选A 这个说不选A??

isabellazyt

你看错答案了吧，就是选B啊

像风一样离去

答案是B啊。