The Smithsonian Museum of Natural History recently unveiled a new

Question

The Smithsonian Museum of Natural History recently unveiled a new exhibit featuring all 225 bones of the fossilized skeletons of two Apatosauruses. Despite the fact that both skeletons are from the same species, one has a tail almost one meter longer than the other.

Which of the following, if true, is the least reasonable explanation for the differences in tail length of the Apatosaurus skeletons described in the passage above?

(A) The skeleton with the longer tail is from an animal that lived 2 million years before the one with the shorter tail.

(B) Scientists believe that Apatosauruses would sometimes shed part of their tail in an attempt to escape a predator.

(C) One skeleton is of an immature Apatosaurus while the other is from an adult male.

(D) One skeleton belonged to a male while the other belonged to a female.

(E) Scientists believe that Apatosauruses generally grew in size according to the food supply available in their environment.

GoSatyen · Answer

All option talk/mention directly about the size or the tail except D.

Can anyone explains me why  B  is correct and  D  is incorrect?

Aviral1995 · Answer

VeritasKarishma   jennpt   AjiteshArun   nightblade354  could you please help me with this question, how to eliminate options?

Fatineel · Answer

This is one of those questions where there are some twisted logic and assumptions.

I originally hesitated between A and B until i read the passage again and found " all 225 bones" which means that essentially the fossilized Apatosauruses did retain their full skeletons so it's kind of unreasonable to think that one of them had it's tail "cut" but then i should assume that tails have bones.
(this is a pretty meager attempt to explain my reasoning

)

To be honest, I would really love to know if the gmat test has these types of questions, I personally find the OG CR questions and answers way more "straightforward" logic than those of prep companies.

) To be honest, I would really love to know if the gmat test has these types of questions, I personally find the OG CR questions and answers way more "straightforward" logic than those of prep companies.

rs045871 · Answer

(A) The skeleton with the longer tail is from an animal that lived 2 million years before the one with the shorter tail.--> possible; may be evolution made the tail bigger

(B) Scientists believe that Apatosauruses would sometimes shed part of their tail in an attempt to escape a predator.-->Doubtful that a bone can be shed; As far as I know, only skin can be shed.

(C) One skeleton is of an immature Apatosaurus while the other is from an adult male.-->possible; one might be a fully grown adult while the other one is not

(D) One skeleton belonged to a male while the other belonged to a female.-->possible; some animals or parts of animals do differ in size between a male and a female

(E) Scientists believe that Apatosauruses generally grew in size according to the food supply available in their environment.-->possible;

StillON · Answer

I think it's B because it is given they have all 225 bones from both the animals, so even if one would have shed a part of its tail then the number of bones would have been different for the 2 animals (obv they cannot break the part of their bone and run away)

Palak74 · Answer

I think the answer is B because it focuses on the Tail only. 
In other options if the two are male/female or adult/immature then the tail should not be the only bone which should have a difference. Other bones of the body should also show the difference.

For option A : if it said that the difference in evolution periods makes a difference in the bone size then it would make some connection to the statement. This option as is would become an assumption that we are adding.

Hence B seems to be the most logical answer

Ozzy11100 · Answer

Ehh... another question of questionable (imo) quality from a 3rd party provider.

I understand the question writers logic, but it's a hell of an assumption  to assume that an animal CAN'T shed a bone fragment when escaping from a predator.   Which is the premise upon which the OA rests.

Like,  who among us can say with certainty that that's a valid assumption? Why couldn't they shed a bone fragment? The bones of the tail could be in sufficient excess of 1 meter long. Who's to say that they aren't? I doubt there are many zoologists/palaeontologists here.

Basically, the OA requires us to make certain fairly unrigorous assumptions to rule out the other answers,  yet requires us NOT to make similar assumptions about the correct answer.  It's a bit like having your cake and eating it too!

A decent try, but another swing and a miss, nevertheless, in my opinion.

ShreyasJavahar · Answer

I did initially use the reasoning that an animal doesn't "shed" something that is on the inside. By definition, shedding is the sloughing off of an external layer or component.
Another run-through of the passage revealed a stronger reason for B to be the answer. The phrase "all 225 bones" implies straight away that there are no bones missing from either fossil, so regardless of any presupposed zoological acumen, option B has the least bearing on why one fossil's tail is shorter. The fact that no bones are absent from either fossil tells us that neither animal lost part of its tail by the evasive manoeuvre outlined in B.

I'd like to hear your points of agreement/disagreement so we can get to the bottom of this question.

Ozzy11100 · Answer

Hey mate,

The crux of my criticism rests on this assumption, as you've made, that, "The fact that no bones are absent from either fossil tells us that neither animal lost part of its tail by the evasive manoeuvre outlined in B." I'm saying it's not unreasonable to believe that an animal could lose part of it's tail WITHOUT losing bones, i.e. it loses part of a bone - total number unchanged.

In light of this, I think the arguments for/against the OA's correctness are largely semantic, and that one could make similar arguments to justify the correctness of the remaining answer choices.

ShreyasJavahar · Answer

Ah alright, I see what you mean. It is a bit of a reach though, one shouldn't have to look at answer choices with such a nuanced perspective. But then again, option A warrants quite a reach as well, and that wouldn't have been the case with an official question. I see your point. Cheers.

SomyaJoshi · Answer

sir, I am perplexed, how can B the answer? like lizards have the same feature to shed their tail and probably 1st time a part of their tailbone is also shed. so please elaborate the answer to me

The Smithsonian Museum of Natural History recently unveiled a new

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