Millions of female bats rear their pups in Bracken Cave.

Question

Millions of female bats rear their pups in Bracken Cave. Although the mothers all leave the cave nightly, on their return each mother is almost always swiftly reunited with her own pup. Since the batsâ€™ calls are their only means of finding one another, and a bat pup cannot distinguish the call of its mother from that of any other adult bat, it is clear that each mother bat can recognize the call of her pup.
The argument seeks to do which one of the following?
(A) derive a general conclusion about all members of a group from facts known about representative members of that group
(B) establish the validity of one explanation for a phenomenon by excluding alternative explanations
(C) support, by describing a suitable mechanism, the hypothesis that a certain phenomenon can occur 
(D) conclude that members of two groups are likely to share a certain ability because of other
characteristics they share
(E) demonstrate that a general rule applies in a particular case

cracker_jack · Answer

I think the answer is A

A) The author derives conclusion from bats in Bracken Cave...
B) The author mentions that "batsâ€™ calls are their only means of finding one another" implying that there are no alternative explainations
C) "phenomenon can occur" seems to say that it may not occur all times
D) there are no two groups. Also, if two groups are mother bats and pups, this tends to contradict author's statements
E) This is not a general rule

shalinikhatri · Answer

I am confused between A and D 

D because there are two groups , one mother bats another pups.

and since pups can not distinguish the calls so mother have the ability to distinguish.

correct me if i am wrong.

gmat2me2 · Answer

A it is

doloris · Answer

It is A.

The author has only evidence about female bats in braken caves.He goes on to derive a general conclusion from this. Best.

meenu · Answer

I think it is C

In A, there is no mention that the mother bat of the Bracken Cave can recognize the call of her pup so, how the argument be generalization of facts known abt a specific group?

amit_drummer · Answer

A

christoph · Answer

B)..."establish the validity of one explanation for a phenomenon by excluding alternative explanations". the argument gives only one explanation for the phenomenon, but there might be more explanations. we dont know. but by not mentioning other explanations the author establishs the validity of his explanations. so B) just doesnt mention other reasons and thats how he is reasoning.

IMO A) is out because he only speaks of one group, the femal bats, that is the representative group. he does not speak of all members.

Arsene_Wenger · Answer

(B). agree with chris.

aceupgmat · Answer

Yes OA is B

DLMD · Answer

B, agree

doloris · Answer

Hey chris! i am more than convinced after reading your explanation .

Can u elaborate more on the error in reasoning of a.who are 'all the members' and who are 'representative members' in this particular case?

Best.

christoph · Answer

the representative group are female bats. the author states that each female bat can recognize the call of her pup. when the author would state as a conclusion that all female mammals can regognize their pup, A) would be right. the goup would be female mammals and this group would be represented by female bats. so its enough to analyse this subgroup and to come to this conclusion because the subgroup is representative. but thats not how the author reasons.

mirhaque · Answer

I think it's B. if you exclude pups ability to id their mothers, it must be the mothers who can successfully identify them to reunite with them at the end of the night.

cracker_jack · Answer

Sometimes we tend to ignore the more obvious answers...like B. The author clearly says that "batsâ€™ calls are their only means of finding one another" thus excluding alternate explainations.

dobb · Answer

Good explanation Christoph

Millions of female bats rear their pups in Bracken Cave.

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