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raconteur
One of the earliest known birds with a beak and contour feathers, Confuciusornis sanctus, had large clawlike “thumbs” on its wings, probably to help it climb up to a launching position for

But why it is not "probably helps it..." or not "prbably helping..."? Thanks!
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sondenso
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One of the earliest known birds with a beak and contour feathers, Confuciusornis sanctus, had large clawlike “thumbs” on its wings, probably to help it climb up to a launching position for

But why it is not "probably helps it..." or not "prbably helping..."? Thanks!

Hi Sendoso,

It's a matter of POE to answer this.

A and B are wrong because "with a beak and contour feathers, Confuciusornis sanctus, with large clawlike..." is awkward. If it was going to keep this pattern, then it shouldn't separate beak, feathers and clawlike "thumbs".... they should all be listed together. So this rules out A and B because "had bla blah blah..." is correct.

E is out because "their" (plural) doesn't agree with birds/Confuciusornis sanctus (singular; "birds" here is singular). So E is gone.

Now, only left with C and D. Your idea of "probably helps it..." or "probably helping..." would work, IF either of those were an option. But their not. So we're left at choosing between C "...which probably helped them" or D "probably to help it". In C, "them" (plural) doesn't agree with "Confuciusornis sanctus" (singular), so C is eliminated. Only thing left is D, which works just fine ("it" is singular and refers back to the bird which is also singular). Although D may not be the way I would say this, after POE, it's clear that D is the only clear and concise answer choice.

Hope this helps!
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sondenso
One of the earliest known birds with a beak and contour feathers, Confuciusornis sanctus, with large clawlike “thumbs” on its wings, which probably helped them to climb up to a launching position for flight.

A. with large clawlike “thumbs” on its wings, which probably helped them to
B. with large clawlike “thumbs” on their wings, which probably helped it to
C. had large clawlike “thumbs” on its wings, which probably helped them
D. had large clawlike “thumbs” on its wings, probably to help it
E. had large clawlike “thumbs” on their wings, probably to help it

You may easily find the correct choice, but can you help me what "probably to help it" in D and E refer to or modifies? Thanks

B, E are out --> Sub-Verb agreement. Singlular Subject (one of the birds.. Confuciusornis sanctus.. is)
A,C are out-- them vs it (shuld be singlular)


D is Correct answer
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Actually it is singular because of the of the subject ONE...

One of the earliest known birds with a beak and contour feathers

Remember to eliminate the middleman...
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Both A and B are fragments. In C, 'its and them' is pronoun mismatch. As also in E, 'their and it' is a mismatch. D is the winner.
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One of the earliest known birds with a beak and contour feathers, Confuciusornis sanctus, with large clawlike "thumbs" on its wings, which probably helped them to climb up to a launching position for flight.

A. with large clawlike "thumbs" on its wings, which probably helped them to
B. with large clawlike "thumbs" on their wings, which probably helped it to
C. had large clawlike "thumbs" on its wings, which probably helped them
D. had large clawlike "thumbs" on its wings, probably to help it
E. had large clawlike "thumbs" on their wings, probably to help it

Confuciusornis sanctus is a singular noun which must be referd to by 'it'.Their and them is wrong and so are A,B,C and E

Option D is the correct answer
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@daagh sir,

Shouldn't comma after Confuciusornins sanctus be also underlined ?
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ankujgupta
daagh sir,

Shouldn't comma after Confuciusornins sanctus be also underlined ?

I can understand why you say so. But you may as well consider that "One of the earliest known birds with a beak and contour feathers" is the subject and "Confuciusornis sanctus" is the modifier (appositive) for the subject. If the comma were not there, then the roles would be reversed.
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Hi Gmatninjatwo,
Is which correctly used on Option C, but issue with plural them?
We need singular pronoun IT to refer to the bird.
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Hi Gmatninjatwo,
Is which correctly used on Option C, but issue with plural them?
We need singular pronoun IT to refer to the bird.


Hello adkikani /Arpit,

I would be glad to help you with this one. :-)

IMHO, use of which is not an issue in Choice C because it is an established fact that birds use wings for flight. Hence, logically, which refers to a slightly far-away noun large clawlike "thumbs".

This sentence purely tests pronoun. Only the correct answer Choice D uses the correct pronoun pair - its and it. Rest all the four options have singular-plural pronoun pair used for the same noun entity.

Hope this helps. :-)
Thanks.
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Hi daagh

What is ", probably to help it" in option D? Usually comma before infinitive is wrong. I'm not sure how adding adverb "probably" changes the situation, as I understand it modifies "to help" itself.

Thanks
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If there is no comma before 'probably,' then the phrase 'probably to help it ' will modify the wings rather than the thumbs.
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One of the earliest known birds with a beak and contour feathers, Confuciusornis sanctus, with large clawlike “thumbs” on its wings, which probably helped them to climb up to a launching position for flight.

A. with large clawlike “thumbs” on its wings, which probably helped them to
(1) pronoun/antecedent problem: the subject is “Confuciusornis sanctus” (singular) but we have “them” (plural) attempting to refer back to the singular subject.
(2) missing an action: this is an incomplete sentence

B. with large clawlike “thumbs” on their wings, which probably helped it to
(1) pronoun/antecedent problem: the subject is “Confuciusornis sanctus” (singular) but we have “their” (plural) attempting to refer back to the singular subject.
(2) missing an action: this is an incomplete sentence

C. had large clawlike “thumbs” on its wings, which probably helped them
(1) pronoun/antecedent problem: the subject is “Confuciusornis sanctus” (singular) but we have “them” (plural) attempting to refer back to the singular subject.

D. had large clawlike “thumbs” on its wings, probably to help it
best option

E. had large clawlike “thumbs” on their wings, probably to help it
(1) pronoun/antecedent problem: the subject is “Confuciusornis sanctus” (singular) but we have “their” (plural) attempting to refer back to the singular subject.
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ExpertsGlobal5
Dear Friends,

Here is a detailed explanation to this question-
sondenso
Source : GMATPrep Default Exam Pack

One of the earliest known birds with a beak and contour feathers, Confuciusornis sanctus, with large clawlike “thumbs” on its wings, which probably helped them to climb up to a launching position for flight.

(A) with large clawlike “thumbs” on its wings, which probably helped them to

(B) with large clawlike “thumbs” on their wings, which probably helped it to

(C) had large clawlike “thumbs” on its wings, which probably helped them

(D) had large clawlike “thumbs” on its wings, probably to help it

(E) had large clawlike “thumbs” on their wings, probably to help it

You may easily find the correct choice, but can you help me what "probably to help it" in D and E refer to or modifies? Thanks

Concepts tested here: Pronouns + Grammatical Construction

A: This answer choice incorrectly refers to the singular noun "Confuciusornis sanctus" with the plural pronoun "them". Further, Option A fails to form a complete sentence; as "helped" and "climb" are both parts of a modifying phrase, there is no active verb to act upon the subject noun "Confuciusornis sanctus".

B: This answer choice incorrectly refers to the singular noun "Confuciusornis sanctus" with the plural pronoun "their". Further, Option A fails to form a complete sentence; as "helped" and "climb" are both parts of a modifying phrase, there is no active verb to act upon the subject noun "Confuciusornis sanctus".

C: This answer choice incorrectly refers to the singular noun "Confuciusornis sanctus" with the plural pronoun "them".

D: Correct. This answer choice correctly refers to the singular noun "Confuciusornis sanctus" with the singular pronouns "its" and "it". Further, Option D acts upon the independent subject noun "Confuciusornis sanctus" with the active verb "had" to form a complete thought, producing a complete sentence.

E: This answer choice incorrectly refers to the singular noun "Confuciusornis sanctus" with the plural pronoun "their".

Hence, D is the best answer choice.

All the best!
Experts' Global Team

Isn’t “Confuciusornis sanctus ” an appositive?

Shouldn’t the Subject, for purposes of the core sentence structure, be:
“One of the earliest known birds with a beak and contour feathers”

in which the head noun (“one”) is singular for purposes of subject-verb agreement?

I understand one obtains the same answer, but it is important to note that the Subject of the main, independent clause is never found in a non essential appositive.

All the best!

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sayantanc2k
ankujgupta
daagh sir,

Shouldn't comma after Confuciusornins sanctus be also underlined ?

I can understand why you say so. But you may as well consider that "One of the earliest known birds with a beak and contour feathers" is the subject and "Confuciusornis sanctus" is the modifier (appositive) for the subject. If the comma were not there, then the roles would be reversed.

As properly stated here by sayantanc2k

Posted from my mobile device
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