Tough CR - Knewton

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Tough CR - Knewton

by voodoo_child » Thu Jun 09, 2011 3:29 pm
Splint bones in the front legs of horses serve only to absorb shock to the front feet. This shock is generated only because horses run. Thus, the fact that Eohippus, an ancestor of the horse, has similar bones in its front legs provides evidence for the hypothesis that Eohippus moved by running, not just by walking.

Which of the following, if true, most seriously weakens the argument in the passage?


(A) Eohippus' splint bones were far more similar to the splint bones of modern horses than to the splint bones of elephants, which usually walk.

(B) It is unknown whether ancestors of the modern horse other than Eohippus had bones similar to splint bones in their front legs.

(C) The mechanism used by horses for absorbing shock could, theoretically, work for similar creatures such as Eohippus.

(D) Not all horses that have splint bones to absorb shock live in regions where the hardness of the ground is similar to that in the regions inhabited by Eohippus.

(E) Other ancestors of the horse that moved only by walking had bones in their front legs similar to those that Eohippus had.


Please explain your answer!

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by LIL » Thu Jun 09, 2011 3:55 pm
(e)

the passage says this:

horses' legs today have special bones which allow them to run. eohippus, an ancestor of today's horses, had similar bones in its legs. therefore, eohippus must have used these bones for running.

we want to weaken the argument that eohippus "must have used these bones for running"

(e) says that other ancestors of the horse that moved only by walking also have these bones. this would weaken the argument that eohippus must have used the bones for running, since these other horses moved "only by walking"

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by honeysn » Thu Jun 09, 2011 6:36 pm
I will also go with E

Option E states that other ancestors of horses that moved "only" by walking had similar bones. Thus having the same bone cannot justify that Eohippus moved by running. -> Weakens that argument

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by sunnyjohn » Thu Jun 09, 2011 8:04 pm
I would take this as a Cause-Effect Weakening Question.

Cause : Split bones
Effect : Running, not walking.

Choice (E) correctly weakens the Argument by showing that "Cause occurred but effect did not".

Flaw with other options:
(A) Comparison of Eohippus with modern horse and elephants. ( Elephants ? Unrelated topic)
(B) Split bones in other Other ancestor ( Unrelated topic)
(C) Mechanism of shock absorbing (Unrelated topic)
(D) Location ( Unrelated topic).

Because of unusual language it was little difficult to understand the stimulus, It took me more than 1:20 mins to understand. However options were quite easy to kill.

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by M09 » Fri Jun 10, 2011 7:20 am
voodoo_child wrote:Splint bones in the front legs of horses serve only to absorb shock to the front feet. This shock is generated only because horses run. Thus, the fact that Eohippus, an ancestor of the horse, has similar bones in its front legs provides evidence for the hypothesis that Eohippus moved by running, not just by walking.

Which of the following, if true, most seriously weakens the argument in the passage?


(A) Eohippus' splint bones were far more similar to the splint bones of modern horses than to the splint bones of elephants, which usually walk.

(B) It is unknown whether ancestors of the modern horse other than Eohippus had bones similar to splint bones in their front legs.

(C) The mechanism used by horses for absorbing shock could, theoretically, work for similar creatures such as Eohippus.

(D) Not all horses that have splint bones to absorb shock live in regions where the hardness of the ground is similar to that in the regions inhabited by Eohippus.

(E) Other ancestors of the horse that moved only by walking had bones in their front legs similar to those that Eohippus had.


Please explain your answer!
IMO E

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by vishalkc2 » Fri Jun 10, 2011 10:29 am
OMO E