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Helr-CR-001

In Guatemala, archaeologists discovered that some fossils of ancient Elaphurus davidianus, an ancient deer in America, have some severe impairment on forehead of the deer. Clearly, therefore, since in the period when the ancient deer lived only the Maya used the trap that first struck the forehead of the prey, the fossils archaeologists discovered must be those of Maya’s prey.

Which of the following, if true, most weakens the argument above?

A. Some of ancient Elaphurus davidianus do have innate impairment on forehead.
B. The acid rain in Guatemala did not make additional damage on the fossils of ancient Elaphurus davidianus.
C. A great many Maya hunters, who frequently used the trap, lived in Guatemala.
D. Even if the ancient deer was struck by the trap, there would have been no treatment for it available in the period it lived.
E. The trap Maya used could not impair the preys to the extent comparable to that of archaeologist’s discovery

Helr

Situation:

考古学家发现了一些麋鹿的化石的头部有一些损坏。因为当时只有玛雅人的陷阱是打击猎物头部的，所以考古者们断定这些化石是玛雅人的猎物的化石。

Reasoning：

Which of the following, if true, most weakens the argument above? 这道题目是一个削弱类题目。需要对论证的推理部分做出削弱。这道题目的结论是因为只有玛雅人攻击头部，所以这些肯定是玛雅人猎物的化石。如果研究发现，玛雅人的陷阱打击猎物的头部没错，但是却不能令猎物的头部受到和发现的化石一样重的伤，这足够可以说明，这个结论可能是有问题的。

-----

A. 一些麋鹿有天生的缺陷。这其实可以有略微的削弱，但是这一些不一定是考古学家发现的那些。所以这个选项不是答案。

B. 酸雨没有给这些化石带来额外的损坏。这个选项是一个加强选项。如果酸雨带来了损坏，就不能说明这些麋鹿化石的损坏是玛雅人陷阱造成的了。

C. 许多玛雅猎人住在G这个地方。这个与论证中的推理部 分无关。

D. 就算麋鹿的头部被打击了，在当时没有任何的治疗手段。就算当时有治疗手段，也不一定会给 这些鹿治疗。

E. 正确。玛雅人的陷阱打击猎物的头部，但是却不能令猎物的头部受到和发现的化石一样重的伤。这点可以削弱整个推理，因为如果受伤的程度不同，可能这些鹿就不是玛雅人捕的，这个推理也就不成立了。

兔美酱

参与讨论
我选A！
题干：在G，考古学家发现了小E的化石，他们前额有损伤。而在那段时间，因为只有玛雅人会给他们带来这种损伤，所以发现的化石是玛雅人的猎物。
WEAKEN
A.有些小E本身前额就有这种损伤。所以不一定有这种损伤，就能说明是玛雅人造成的。削弱推理。可以留下
B.说是酸雨没有造成这种损伤。【噗..那也玛雅人没得关系啊！  选不得！
C.只说玛雅人住在G，没说前额损伤的事  不选！
D.治不了它.. 和推理的逻辑链好像扯不上关系。... 也不选
E.玛雅人造成的损伤 到不了化石上的损伤那种程度。   提到了前额损伤的事.可以留下
下面比较A和E：
A的观点是，损伤是小E天生的，与玛雅人无关。E选项则是说玛雅人造成的损伤不及化石上的损伤的那种程度。说实话..我觉得两个选项都可以削弱推理，但是感觉E选项里引入了一个损伤程度的因素，而A始终围绕小E和玛雅人在说事..所以吧。。我还是选A了！
请指教！谢谢！

lixuekai2001

参与讨论

此CR的结论是the fossils archaeologists discovered must be those of Maya’s prey.
比较AE:
A: 有些麋鹿天生前额有伤痕。（姑且承认历史上确实有天生带伤痕的麋鹿，但也可能考古家发现的麋鹿伤痕恰好正是玛雅人给造成的，如果是，那么A即可排除。）
E:  玛雅人给麋鹿造成的伤痕远没有考古家发现的伤痕严重。

选E.

babybearmm

参与讨论
选E


Weaken
Premise 1: In G, archea find fossils of ancient dears: injury at forehead
Premise 2: at that time, only the Maya used the trap that injure the forehead
Conclusion: the fossil dears = Maya's prey


okay, it seems that the author assumes: the way Maya prey the dear was THE ONLY REASON for the forehead-injury found on the fossil.
When reading I notice that Premise 2 says "at that time" (original words "in the period the ancient deer lived"). There's a huge gap! What if the forehead-injury found on the fossil did not occur at that time? (For example, the fossil could be damaged at forehead over the long long history when buried underground)


A. "some ... innate impairment on forehead" - maybe... keep this on
B. "no additional damage" - wow! that was exactly what I think! BUT, this STRENGTHENS the argument!
C. again, this makes the conclusion more likely. STRENGTHEN
D. "If dear was struck by trap, no treatment available" ... If anything, this strengthens the argument by showing that the forehead-injury left untreated.
E. this strongly suggests OTHER factors take in part. consistent to my prediction.

Look back at A... oh i see!! the question says "severe impairment", but choice A does not say the innate impairment is severe. Even if the dears have innate impairment, it could also be the hunters who causes the additional impairment (to reach a "severe" level). So Choice A does not challenge the conclusion. Choice E does a great job in stating the "extent" of impairment.

Helr-CR-1

In Guatemala, archaeologists discovered that some fossils of ancient Elaphurus davidianus, an ancient deer in America, have some severe impairment on forehead of the deer. Clearly, therefore, in the period the ancient deer lived, since only the Maya used the trap that first struck the forehead of the prey, the fossils archaeologists discovered must be those of Maya’s prey.
Which of the following, if true, most weakens the argument above?
A. Some of ancient Elaphurus davidianus do have innate impairment on forehead.
B. The acid rain in Guatemala did not make additional damage on the fossils of ancient Elaphurus davidianus.
C. A great many Maya hunters, who frequently used the trap, lived in Guatemala.
D. Even if the ancient deer was struck by the trap, there would have been no treatment for it available in the period it lived.
E. The trap Maya used could not impair the preys to the extent comparable to that of archaeologist’s discovery

-- by 会员 GMAT (2012/7/2 22:11:56)

erok

参与讨论
E
类型是相关到因果
deer化石严重伤←→只有maya伤猎物
因果结论：deer是maya的猎物
CQ是相关性存在问题
BCD都是加强相关性
A的话我觉得有两点不好，一个是some，有可能会产生枚举的错误；一个是没有说"severe"。所以没有攻击到相关性
E的话直接说明两者相关性有问题，或者按照之前很火的“有因无果”来解释，也是一个意思

adriana2011

Helr-CR-1
In Guatemala, archaeologists discovered that some fossils of ancient Elaphurus davidianus, an ancient deer in America, have some severe impairment on forehead of the deer. Clearly, therefore, in the period the ancient deer lived, since only the Maya used the trap that first struck the forehead of the prey, the fossils archaeologists discovered must be those of Maya’s prey.
逻辑链：
前提： some fossils of 一种deer 头部有一些严重的损伤；那时期只有Maya人用trap first stuck the forehead
结论：这些deers的化石一定是maya人捕猎的deer的化石

A. Some of ancient Elaphurus davidianus do have innate impairment on forehead.   有点干扰。
B. The acid rain in Guatemala did not make additional damage on the fossils of ancient Elaphurus davidianus.  有点加强的感觉
C. A great many Maya hunters, who frequently used the trap, lived in Guatemala.   有点加强的感觉
D. Even if the ancient deer was struck by the trap, there would have been no treatment for it available in the period it lived.   受伤后是否治疗 无关
E. The trap Maya used could not impair the preys to the extent comparable to that of archaeologist’s discovery.   maya人用trap struck deers的损伤程度无法达到考古学家发现的那些损伤的程度。 原文前提的severe似乎也暗示e 是正确选项！

cry4stal

E
A中说Some ... have innate impairment on forehead, 这与 some severe impairment on forehead of the deer是Maya人造成的并不矛盾，因此不能起到削弱作用
E中Maya人的impair程度没有考古学家发现的深，所以这些severe impairment可能不是Maya人造成的。

frankiyian

同选E
P: Fossil have SEVERR impairment on forehead, ONLY Maya can give that struck -----> C: Dears are Maya's prey
Focus: What caused the impairment?
B,排出他因，加强。
C,直接加强premise
D,IRRELAVENT
三个LOSER，剩下AE直接攻击到FOCUS。
A的socpe有问题，some of。。。 innate impairment
E相对较完美 - -

glhelr

这道题目不是道难题哦~~~加油加油~~