94) Chris and Emma will represent Don Bosco School in the

This doesn't sound like a very GMAT-like question. Where is this from?

I go with D as it is the most concise and grammatically correct

D it is . "contest, for their work as public speakers has been excellent this year"
"this" is ambiguous

General: 1. 'this'—use of a demonstrative pronoun as ‘this’ without an accompanying noun is incorrect. However, it is not a critical issue in this case, as all the choices indulge in the same.
2. In D and E, the meaning is substantially altered. Participating in an elocution contest is not the same as work as public speakers.

(A) Contest, their work in this having been excellent this year –
This is a simple sentence followed by an appositive modifier. Other than calling it backward and strange, can any grammatical error be pointed out? What is grammatically wrong in this choice?

(B) contest; they have done excellent work this year in this – This is not a fragment; a semi colon is used to separate two independent cl but somewhat related clauses, and that requirement is fulfilled here. A fragment results, when you do not have a working verb; ‘have done ‘is the working verb for the second arm. What is grammatically wrong in this choice?

(C) contest, for this year they have done excellent work in this---- I can’t fine fault with this also, since the second indepencdent cluse is joined by a 'fanboys' conjunction and is duly separated by a comma before. What is grammatically wrong in this choice?

(D) contest, for their work as public speakers has been excellent this year – work as public speakers is different from participating in an elocutioncontest. Intent is seriously altered. But grammar is ok; may be the voice is passive. We can confidently
reject it.
(E) contest; their work as public speakers having been excellent this year – Same as D and the second part after the semi colon does not have working verb; hence a fragment. We can simply dump it.

Among A, B and C –Which two can be eliminated? I feel all the three are beautiful and grammatically proper constructions in their own right. Hence, this seems to be a weird example. I have not seen a GMAT issue with so much of touch – and - go and photo-finish, unless the author has some bigger issue up his sleeve. In that case, I couldn’t be more curious to know it?

Answer is A.

I think OA is wrong.

In my opinion,
The answer is D.
Its crisp and concise.

Ok, I am just going to say it. This is not a GMAT style question and the answer choices are odd. The GMAT style of written English is much more American influenced. This has obviously been crafted by some teaching institute in India, and the sub-continent style of writing is evident in the answer choices.

A is probably the least offensive of the lot, but again, like I said, having looked at lots of official material, one does not see GMAT structuring their SC in this manner. Usually the very difficult ones will bring you down to 1-2 and then make it much harder to choose, but a high level scorer will still pick out the correct choice. This one, on the other hand, is a lot more ambiguous. The use of "This" here is not standard and something very unlikely to appear on a GMAT question.