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

This is GMATPREP question. What is wrong with answer "E" and why answer "D" is correct?

Is it possible to answer this question or is this a banned source too ??



Speaking of banned sources, are there any more sources out there that are still not considered as a "black list" and can be discussed on this forum.

I truly believe that Stacy and Ron are the best tutors any student preparing for GMAT can have. I personally have improved my score on SC from a paltry 30-32% to an approximate 75+% hit ratio now. Have probably gone through each and every post of the Verbal(SC) question on this forum and diligently prepared notes etc. It truly helped me grasp the concepts etc.....and now I am digressing...:-)

It is real sad to see that we cannot discuss any more questions on this forum.....

In any event thank you Stacy & Ron.....you guys rock!!!!

nah, we can answer these; the OP just happened to post an enormous number of problems on the same day, so we ignored them over a certain maximum # so that we could allot some of our attention to other posters' material.

the Stickies at the top of each thread contain a list of banned sources. if your source isn't in the list, you can assume that it's ok.

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breakdown of the above problem:
(a), (b)
these aren't sentences at all, since neither of them has a main verb.

(c), (e)
inconsistent pronouns: in (c) 'it' suddenly changes to 'them', and in (e) 'them' suddenly changes to 'it'.
in fact, you can eliminate ALL of the wrong answer choices on this pronoun issue alone; note that choice (d) is the only one of the five that contains consistent pronouns.

note that the pronouns MUST be singular, anyway, because they refer to 'one of the earliest known birds...' so even if you had an answer choice with both 'their' and 'them', it'd still be wrong.

Thanks...

All question seem so obvious after one sees the explanation..... :)