[求助]GWD3-Q5???!!!

mm007_mmgmat

[求助]GWD3-Q5求解

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

 

这是为什么呢？？？

不选A?原文定位的依据在哪里？？？？

在线等啊

stellachan

应该就是选A吧

stellachan

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.

1994年the McKay team开始研究 ALH84001，2年后，提出这个发现。

一般人按照这个思路说，都是他们先提出来的吧。

题目问的也只是assert

jamily_2008

选B:依据: which scientists generally agree originated on Mars,大家都普遍同意=B:这个问题不是科学界争论的话题

A错误:既然"ALH是在火星上被发现的"已经被广大科学家所认同,那这个发现就一定是在该小组进行研究之前就被提出过了.

bonniehuster

我不是太明白为什么是定位这句话呀，这句话说的是来自火星这件事情，不是说“里面有生物”这件事情啊。而文章在讲的是关于里面的生物是不是来自火星吗。为什么选B，而不是C呢。。。能帮我解释一下吗~~

bonniehuster

噢哟，明白了，自己回答自己吧。题目问的只是来自火星这个assertion...做题目做昏头了...不好意思大家

clara823

我不明白为什么E不对呢 ？第二段的For example 后面提出ALH84001 has been on earth for 13,000 years 这点确实质疑了ALH84001 originated on Mars啊！！大家快来帮帮忙啊 急于求解 ！谢谢了

superfanluyao

选A吧 没什么问题

sm913

选A吧 没什么问题

-- by 会员 superfanluyao (2010/8/1 23:20:53)

the McKay team announced that ALH84001, which scientists generally agree originated on Mars
这句话说明在MCKAY之前，SCIENTIST已经普遍认可 originated on Mars 了。所以不能选A

像风一样离去

C项行不行呢？