A. The ophthalmologists' offices have begun selling prescription goggles to their customers once the nearby gymnasium had completed adding an Olympic size outdoor pool --- beginning of selling is an one-time affair; Hence, we need a simple past to describe that. Wrong

B. The ophthalmologists' offices began the selling of prescription goggles to their customers once the nearby gymnasium had completed adding an Olympic size outdoor pool … began the selling is unidiomatic
C. That ophthalmologists have begun the selling of prescription goggles to their customers once Olympic pool the nearby gymnasium had completed adding ---- 1 a fragment 2. Ophthalmologists have not begun; their offices did. --- Distortion of the original meaning


D. The ophthalmologists began selling prescription goggles to their customers once the nearby gymnasium had completed adding an Olympic size outdoor pool ….. Distorted version. It is the offices that began selling; not the ophthalmologists themselves

E. That ophthalmologists' offices began selling prescription goggles to their customers once the nearby gymnasium had completed adding an Olympic size outdoor pool – best on all counts tense usage and keeping intact the meaning.

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Narendran +9198845 44509

You are right. I misread that for the
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you can know a lot about something and not really understand it."-- a quote
No one knows this better than a GMAT student does.
Narendran +9198845 44509

The goggles in question are prescribed by the ophtalmologists and sold in their offices not by their offices.

I see a 3/2 split. With A, B and E using a form of "ophthalmologists' offices" selling the goggles. This doesn't make sense and its a bit awkward since the offices are selling the goggles and not the ophthalmologist.

In C, the use of that at the beginning is awkward and unidiomatic. Therefore, we are left with D which is clearer and to the point.

Based on a webinar I attended yesterday, I believe that we have to pick an option which is logically in sync with the original sentence. So, ideally we have to pick an answer choice which is logically similar to the original sentence and is grammatically correct.
Is my above statement correct? If it is, saying that ophthalmologists selling the goggles change the logic of original sentence(which conveys that office is selling goggles).
Option B retains the logic of the original sentence. 'began the selling of' might be a bit verbose but it seems to be grammatically correct. Shouldn't this mean that B is the only option which is both logically in sync with the original sentence and grammatically correct as well?

Could someone please comment on it.

Thanks

I misread That as The in E and opted E. Now i see why D is right answer .