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Bunuel
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Over the past five years, the quality of synthetic diamonds — first pr 23 May 2018, 23:15
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91% (00:44) correct 9% (00:50) wrong based on 210 sessions

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Over the past five years, the quality of synthetic diamonds — first produced in the 1950s for industrial uses such as cutting and polishing — have increased so much that many experts cannot differentiate between synthetic diamonds and real ones.


A. have increased so much that many experts cannot differentiate between synthetic diamonds and real ones

B. have increased to such a large degree that some experts cannot differentiate synthetic diamonds from real ones

C. have increased so much that some experts cannot differentiate synthetic diamonds from real ones

D. has increased so much that some experts cannot differentiate synthetic diamonds from real ones

E. has increased to such a large degree that some experts cannot differentiate synthetic diamonds between real ones
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D
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Over the past five years, the quality of synthetic diamonds — first pr 23 May 2018, 23:36
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IMO ans is D
Subject quality of synthetic diamonds - requires singular verb has, so A, B, C are out.
E uses wrong idiom differentiate A between B.

So D best choice.
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Over the past five years, the quality of synthetic diamonds — first pr 23 May 2018, 23:58
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Bunuel
Over the past five years, the quality of synthetic diamonds — first produced in the 1950s for industrial uses such as cutting and polishing — have increased so much that many experts cannot differentiate between synthetic diamonds and real ones.


A. have increased so much that many experts cannot differentiate between synthetic diamonds and real ones

B. have increased to such a large degree that some experts cannot differentiate synthetic diamonds from real ones

C. have increased so much that some experts cannot differentiate synthetic diamonds from real ones

D. has increased so much that some experts cannot differentiate synthetic diamonds from real ones

E. has increased to such a large degree that some experts cannot differentiate synthetic diamonds between real ones
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Answer should be option D.
The phrase 'quality of diamonds' should be followed by 'has' and not 'have'. So this logic gives us options D & E.
Now, in option E, the part 'cannot differentiate synthetic between real ones' is not correct. Instead of 'between', it should have been 'from' which is the case in option D.
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Over the past five years, the quality of synthetic diamonds — first pr 24 May 2018, 00:03
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Over the past five years, THE QUALITY of synthetic diamonds — first produced in the 1950s for industrial uses such as cutting and polishing — have increased so much that many experts cannot differentiate between synthetic diamonds and real ones.


A. have increased so much that many experts cannot differentiate between synthetic diamonds and real ones

B. have increased to such a large degree that some experts cannot differentiate synthetic diamonds from real ones

C. have increased so much that some experts cannot differentiate synthetic diamonds from real ones

D. has increased so much that some experts cannot differentiate synthetic diamonds from real ones - correct

E. has increased to such a large degree that some experts cannot differentiate synthetic diamonds between real ones
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Over the past five years, the quality of synthetic diamonds — first pr 21 Mar 2019, 01:00
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VERITAS PREP OFFICIAL EXPLANATION

With the clear subject-verb agreement decision point (has vs. have increased) at the start of each answer choice, you should start by analyzing that. To find the proper subject, use the slash-and-burn technique to remove all the modifiers: “the quality…have increased” OR “the quality…has increased.” Since “quality” is singular it must be “has increased” and you can eliminate (A), (B), and (C) confidently.

The choice between (D) and (E) comes down to several differences in diction between the two choices. It is correct to say “differentiate x from y” or “differentiate between x and y” but it is quite clearly incorrect to mix the two: you cannot “differentiate x between y”. Also, “to such a large degree that” is an unnecessarily awkward construction when “so much that” expresses the same meaning. (E) can be eliminated based on these diction errors leaving the correct answer (D), which contains proper subject-verb agreement and concisely expresses the meaning with the proper “so much that” and “differentiate x from y.”
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Over the past five years, the quality of synthetic diamonds — first pr 21 Mar 2019, 03:53
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i answered the question correctly becuase of the SV problem , but wanted to know can "some" replace "many".
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Over the past five years, the quality of synthetic diamonds — first pr 21 Mar 2019, 04:11
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nikhilbhat
i answered the question correctly becuase of the SV problem , but wanted to know can "some" replace "many".
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Yeah that's a good question and honestly I bet the question author didn't even notice that distinction (I know I didn't on first read until I scrolled down and saw your question...that's the danger with getting so good at finding the actionable decision points that you get so focused on those that you barely notice other differences).

I'd consider it a pretty important strategic note that you DO NOT need to worry about "preserving the meaning of A." For whatever reason that becomes a priority for a lot of students but there's no special value to A...it's just one of five proposed ways to express the idea and because so many grammatical errors impact meaning (for example a misplaced modifier is wrong precisely because it creates an illogical meaning) then 80% of the time the meaning of A is flawed and you MUST make some change to that meaning in order to get the problem right. So while like I said in this case I'd bet "some" vs. "many" is an unintentional difference, I still think the lesson holds that I'd never use something like that as a decision point because neither meaning is illogical and there's no rule that you have to uphold the meaning of the original.
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