Question

that
she discovered the double helix.

A) The scientist knew for a long time beyond a shadow of a doubt

B) For a long time, the scientist had known beyond a shadow of a doubt

C) For a long time, the scientist had known with great certainty

D) For a long time, the scientist knew beyond a shadow of a doubt

E) The scientist had known for a long time beyond a shadow of a doubt

anandnk · Answer

One more vote for D.

 "knew"  is apropriate here insteadof  "had known"  because you know only after you discover and not before the discovery.

D is very clear in placing the modifier before the real clause.

kpadma · Answer

Let me play the devils advocate role!

Every one is piling on D!

But "for a long time" warrents a perfect or a progressive tense and 
not defenitely a simple tense. 

I would say D is incorrect for this reason!!

Paul · Answer

For a long time, the scientist knew  beyond a shadow of a doubt that 
she discovered the double helix

is equivalent to

 The scientist has known  beyond a shadow of a doubt that she discovered the double helix

Present perfect tense implies that something happened over a span of time and may still be happening today.

Let me reverse the construction of D

She discovered the double helix and for a long time, she knew  ...

is equivalent to using present perfect:

She discovered the double helix and she has known  ...

Both of the above say that the scientist discovered the double helix at some point in the past and  since then and up until today , she has known it. Obviously, the fact of her knowing it for a long time must have happened after the discovery. Conclusion, D is similar to the usage of present perfect and is thus best

hallelujah1234 · Answer

The latter is not equivalent to the former. Padma's reasoning is valid and within the ambit of standard-rules:)

Skeletor · Answer

Well...even I thought that the answer is D.

But the OA is C.

I do not have an explanation of the answer.

aonie · Answer

Hi, I've been watching this forum for quite sometime and I think i like to contribute my thoughts too....

I think answer C is correct. My 2cents for this question is: 1. "with great certainty" is much more precise than "beyond a shadow of the doubt". It also sounds more formal and less flowery for this kind of topic. 2. Just for making things more clear (although it may look silly), let's try to reconstruct the sentence in present tense: that she discovered the double helix In this sentence, the statement exist only because she had thought about discovering the double helix before she actually discovered the double helix, so the thought must exist before the actual the discovery, and the thought must still be true even in the 0.001 sec before she discovered the helix, which warrants a perfect tense. so in present tense: the scientist has known for a long time, ... that she discovers/will discover the double helix. and in past tense it is true that: the scientist had known for a long time,... that she discovered the double helix. (she would have thought about until she actually discovered it and since it is in past tense we need to use: simple past and past in the past (past perfect).

Praetorian · Answer

Welcome to GMAT Club.

Do participate, its one of the better ways to learn. Guys, about this question, I would be worried if this is of GMAT quality. Sincerely Praet

<The scientist knew for a long time beyond a shadow of a

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