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Perhaps the most significant medical breakthrough of the twenties, the real story behind the isolation of insulin was not revealed for over fifty years .


A)Perhaps the most significant medical breakthrough of the twenties, the real story behind the isolation of insulin was not revealed for over fifty years. (The real story is not the medical breakthrough)
B)The real story behind the isolation of insulin was not revealed for over fifty years, even though it was perhaps the most significant medical breakthrough of the twenties. (Same as A)
C)Although the isolation of insulin was perhaps the most significant medical breakthrough of the twenties, the real story behind it was not revealed for over fifty years. (correct)
D)The real story behind the isolation of insulin was not revealed for over fifty years, although insulin was perhaps the most significant medical breakthrough of the twenties. (Isolation of insulin not insulin)
E)Although insulin was perhaps the most significant medical breakthrough of the twenties, its isolation was not revealed for over fifty years. (same as D)
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C does not make sense whatsover-It was insulin that was the medical breakthrough not its isolation-Only D looks good
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Perhaps the most significant medical breakthrough of the twenties, the real story behind the isolation of insulin was not revealed for over fifty years .

A)Perhaps the most significant medical breakthrough of the twenties, the real story behind the isolation of insulin was not revealed for over fifty years.
The phrase Perhaps the most significant medical breakthrough of the twenties must modify isolation of insulin. It makes no sense for this phrase to modify the real story.
B)The real story behind the isolation of insulin was not revealed for over fifty years, even though it was perhaps the most significant medical breakthrough of the twenties.
This sentence can be rephrased as even though it was perhaps the most significant medical breakthrough of the twenties,The real story behind the isolation of insulin was not revealed for over fifty years. Here again there is modifier error as in choice A. The most significant medical breakthrough was isolation of insulin and the the real story.
C)Although the isolation of insulin was perhaps the most significant medical breakthrough of the twenties, the real story behind it was not revealed for over fifty years.
Correct
D)The real story behind the isolation of insulin was not revealed for over fifty years, although insulin was perhaps the most significant medical breakthrough of the twenties.
Modifier error. Insulin was not the most significant medical breakthrough but the isolation was. We can decide whether it was insulin or isolation of insulin from Choice A which usually provides the intended meaning of the author. So, as per choice A it must be isolation that should be modified and insulin.
E)Although insulin was perhaps the most significant medical breakthrough of the twenties, its isolation was not revealed for over fifty years.
Same error as D change in intended meaning.
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Perhaps the most significant medical breakthrough of the twenties, the real story behind the isolation of insulin was not revealed for over fifty years .

A)Perhaps the most significant medical breakthrough of the twenties, the real story behind the isolation of insulin was not revealed for over fifty years.
B)The real story behind the isolation of insulin was not revealed for over fifty years, even though it was perhaps the most significant medical breakthrough of the twenties.
C)Although the isolation of insulin was perhaps the most significant medical breakthrough of the twenties, the real story behind it was not revealed for over fifty years.
D)The real story behind the isolation of insulin was not revealed for over fifty years, although insulin was perhaps the most significant medical breakthrough of the twenties.
E)Although insulin was perhaps the most significant medical breakthrough of the twenties, its isolation was not revealed for over fifty years.

what is "IT" referring in option C
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A)Perhaps the most significant medical breakthrough of the twenties, the real story behind the isolation of insulin was not revealed for over fifty years.-WRONG: Modifier Error
B)The real story behind the isolation of insulin was not revealed for over fifty years, even though it was perhaps the most significant medical breakthrough of the twenties.-WRONG: 'it' pronoun ambiguity....whether 'it' refers to isolation or to insulin
C)Although the isolation of insulin was perhaps the most significant medical breakthrough of the twenties, the real story behind it was not revealed for over fifty years.-WRONG:same as B
D)The real story behind the isolation of insulin was not revealed for over fifty years, although insulin was perhaps the most significant medical breakthrough of the twenties.-CORRECT: clear...flaw in A, B, and C is resolved
E)Although insulin was perhaps the most significant medical breakthrough of the twenties, its isolation was not revealed for over fifty years.-WRONG: its the story that was not revealed
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ammuseeru
what is "IT" referring in option C
A little( :) ) late, but that it points to the isolation of insulin.
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AjiteshArun

Hi Sir,

I am a little confused with the whole answer here.

In Option C, we are basically saying that “isolation of insulin was perhaps the most significant medical breakthrough”
That doesn’t make sense.

How can “isolation of insulation” be the “most significant medical breakthrough”? Isn’t it the “insulin” that is the “most significant medical breakthrough”?

I believe answer is E

Can you please help here. Between C and E please

Posted from my mobile device
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Vinit800HBS
AjiteshArun

Hi Sir,

I am a little confused with the whole answer here.

In Option C, we are basically saying that “isolation of insulin was perhaps the most significant medical breakthrough”
That doesn’t make sense.

How can “isolation of insulation” be the “most significant medical breakthrough”? Isn’t it the “insulin” that is the “most significant medical breakthrough”?

I believe answer is E

Can you please help here. Between C and E please
Hi Vinit800HBS,

They're asking us to take a meaning call here: is it the substance itself that is the breakthrough, or is its isolation the real breakthrough? Isolation seems to suggest that other things were removed. That is, isolation seems to mean extraction. That sounds like something important.

However, this is not an official question, so it's fine if you feel that the GMAT won't test what sounds a little bit like a technical term.

There is another (more reliable) meaning call we can take here:

C ... the real story behind it was not revealed for over fifty years. ← This seems reasonable. The real story behind the breakthrough was not revealed for a long time.
E ... its isolation was not revealed for over fifty years. ← This option drops the real story bit altogether.

I think it's more likely that it was the story that was kept "secret" for 50 years (otherwise, why would the word "real" be used)? Effectively, option C says that a breakthrough happened in the 20s, but the real story behind that breakthrough came out much later.
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Hello expert,
I think both c and D are in logical meaning and grammatical correctly, so how to make choice in this situation?
Besides, even “it” in C is a bit ambitious, as “it” can only refer to a noun(but not a noun phrase), and there are two nouns(isolation and insulin) in C. So why is C superior than D? Thanks.
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Mavisdu1017
Hello expert,
I think both c and D are in logical meaning and grammatical correctly, so how to make choice in this situation?
Besides, even “it” in C is a bit ambitious, as “it” can only refer to a noun(but not a noun phrase), and there are two nouns(isolation and insulin) in C. So why is C superior than D? Thanks.

Hello Mavisdu1017,

We hope this finds you well.

To answer your query, Option C is superior to D because D alters the intended meaning through the clause "insulin was perhaps the most significant medical breakthrough of the twenties"; the construction of this clause incorrectly implies that the naturally occurring chemical insulin, itself, was perhaps the most significant medical breakthrough of the twenties; the intended meaning is that the isolation of insulin was perhaps the most significant medical breakthrough of the twenties.

Further, there is no rule that says "it" cannot be used to refer to a noun phrase; for example, "The car speeding down Main Street crashed because it hit a pothole."; here, we can say that "it" refers to the noun phrase "The car speeding down Main Street".

We hope this helps.
All the best!
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This question is a little too technical.

"Breakthrough of insulin" is a verb phrase or a noun phrase?

If "Breakthrough of insulin" is a verb phrase, a pronoun (IT) can't refer to it.

While, if "Breakthrough of insulin" is a noun phrase, can it be a breakthrough?

I don't know, quite confusing. :?
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I selected the wrong choice - option D, but after carefully observing the meaning, I got to know this:

Choice D - The real story behind the isolation of insulin was not revealed for over fifty years, although insulin was perhaps the most significant medical breakthrough of the twenties.

Why would the author say something about "isolation of insulin" if his sole purpose was to bring "insulin" to the picture?

Yes, insulin can refer to medical breakthrough but the gist of para is how the "isolation of insulin" was not revealed for so many years, even it (isolation of insulin) was the most significant breakthrough.

Does it make sense?
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