A PhD student at the University of Portsmouth has identified an

IMO D

Pre Think-> So the point was a discovery was made of a species that used to exist at some time in the past

A) existing concurrently with those that did
Eliminated based on Pre Think

B) existing concurrently with those that were
Eliminated based on Pre Think

C) that existed concurrently with those that had
If this statement is without any discrepancy, this didn't make any sense to me, after had there should had been other species.

D) that existed concurrently with other grasshoppers
Simple past tense is apt here.

E) that had existed concurrently with other grasshoppers
Past perfect tense not required, was the discovery not made in the recent time ??
_________________

A) existing concurrently with those that did
B) existing concurrently with those that were
C) that existed concurrently with those that had
D) that existed concurrently with other grasshoppers

E) that had existed concurrently with other grasshoppers

A,B,C and D has either tense problem or vague pronoun.

'E' used the past perfect tense which is the correct one to clarify that the species existed in the past, but no longer present. Also, 'those' is replaced with clear noun

IMO E

IMO Option D is correct.
A,B, and C incorrectly use the wrong tense and "that did" and "that were...that had" are all wrong. Ask yourself, "that were...that did...that had...WHAT in the Cretaceous period"
Option D uses the correct tense and is not ambiguous.
E uses "that had existed" for no reason and hence is also incorrect.

A PhD student at the University of Portsmouth has identified an ancient ancestor of the modern grasshopper, a species of the family Proscopiidae existing concurrently with those that did in the Cretaceous period, approximately 115 million years ago.

We can easily infer from the sentence that the grasshopper existed 115 milion years ago, so A and B with a continuos tense are ruled out.
C does not have a verb for "had" before in.
E is ruled out because the sequence of the events is clear as it is. We don't need the past perfect and the two events are not correlated.
So in my opinion D is the right one

IMO D ,

that existed concurrently with other grasshoppers ; rightly links and modifies a species of the family Proscopiidae

in E usage of 'had' seems wrong and awkward .

A PhD student at the University of Portsmouth has identified an ancient ancestor of the modern grasshopper, a species of the family Proscopiidae existing concurrently with those that did in the Cretaceous period, approximately 115 million years ago.


Meaning analysis: One student has identified one grasshopper. This grasshopper is an ancient ancestor of the modern grasshopper. Moreover the grasshopper that he has identified belongs to a species of the family Proscopiidae. This family species with other family species lived 115 million years ago in the Cretaceous period.

Error analysis: Let's see the sentence structure -->



v-ing modifier without a comma modifies family Proscopiidae and suggests that it is still existing, and general feature of this family, but per the intended meaning of the sentence this species lived 115 million years ago in the Cretaceous period. Hence v-ing is incorrect here.

POE
First split between "existing" and "that existed". (A) and (B) can be eliminated as per meaning analysis.
Eliminate (E) becaouse of "past perfect". Between (C) and (D), (C) out becouse of illogical "had"

A) existing concurrently with those that did
("did" most probably refers to "existing" -> in the past)

B) existing concurrently with those that were
("were" most probably refers to "existing" -> in the past but it is nonsensical)

C) that existed concurrently with those that had
("existed" - past simple we are fine here, "had" what? illogical)

D) that existed concurrently with other grasshoppers



E) that had existed concurrently with other grasshoppers
("had existed"-? we need other time point in the past to use part perfect tense, here all this information is descriptive and we don't need any sequencing of events)

D is the answer
_________________

A PhD student at the University of Portsmouth has identified an ancient ancestor of the modern grasshopper, a species of the family Proscopiidae existing concurrently with those that did in the Cretaceous period, approximately 115 million years ago.

A) existing concurrently with those that did
B) existing concurrently with those that were
C) that existed concurrently with those that had
D) that existed concurrently with other grasshoppers
E) that had existed concurrently with other grasshoppers

OFFICIAL EXPLANATION
My annotations to and edits of the original OE are in blue typeface.

• Because the family Proscopiidae lived in the Cretaceous period, the word existing, which is a present participle, is the wrong tense.
Eliminate A and B

• Now, compare the remaining answer choices.

• Choice C uses a pronoun while D more clearly restates the word grasshoppers, which is both more specific and avoids confusion.
Eliminate C and keep D.

• Option E uses the past perfect. There is no reason to suspect that something happened
before the Cretaceous period, an event that would require the use of the past perfect.
Eliminate E for using the construction had existed.

• The correct answer is D

COMMENTS

That OE is good, except for the analysis of option C.
The author of this OE does not use splits, but rather, takes the answers in order.
If splits are not clear, that method is smart.

Now, analysis of Option C versus Option D:

Yes, the pronoun those in C is "not as clear" as the word grasshoppers in D.

But as Skywalker18 points out, the OE does not articulate the rule clearly.

The antecedent logically should be "grasshopper," which requires a singular pronoun.

"Not as clear" is one reason that pronouns must agree with antecedents.

The ancient ancestor of the modern grasshopper is modified by the appositive "a species of the family XYZ." Multiple choice gives us the chance to avoid deciding the pronoun issue.

With nouns that can be both singular and plural, and when pronouns are at issue, if possible I find another reason to eliminate answers:
-- either another answer is more clear
-- or the option that contains the pronoun question is plagued by another error.

(D) says "grasshoppers."
The other options all include a reference to something plural ("those").

The switch to plural is fine in (D) because the relationship between the initial subject and the plural grasshoppers in a family is clear:
One species of ancient grasshopper existed at the same time as other kinds of grasshoppers.

If a question tests a noun such as species that can be singular or plural (series, data, deer), the GMAT will always provide a clue about whether the noun is singular or plural.
Species is singular, from the article a.

See, for example, this official question, here about tiny, blind catfish.

Some people might be inclined to say that species as singular and those as plural is an obvious error.

I don't think so. When analyzing slowly? Sure. Under the gun of the test timer? Not so much.

(D) is better. I leave pronouns, unless glaringly obvious, until the very end.

The easier-to-spot problem with option C, however, is its ending:
those that had [existed]

-- we have to imagine the implied existed. More work.
-- we have to think about whether past perfect is necessary

In option D, "grasshoppers IN" is perfectly correct, short, and does not involve an extra and somewhat odd verb.

-- In (C) and (E), there is no reason to use the past perfect.

D versus E?

Takeaway: Although we will rarely be in the situation,
(1) if we are faced with one choice that uses only simple past and another choice that uses past perfect;
(2) if past perfect is unnecessary; and
(3) if no other error exists to eliminate one option,
choose simple past.

Almost always, if a sentence is grammatically correct when rendered in simple past only and in
past perfect plus simple past (or time reference), there will be another error in one of the two constructions.

In this case, no other error can help us decide between D and E.

This GMAC preference just needs to be memorized: do not use past perfect if simple past will work.

The emphasis is on preference. What I'm discussing is not a hard-and-fast rule.

Again, if we find ourselves down to two options that pit past perfect against simple past,
look for another error.
If none exists, pick simple past.

KanishkM gets a smiley face for second-best answer and GKomoku gets kudos for best answer.
_________________

A) existing concurrently with those that did

B) existing concurrently with those that were

C) that existed concurrently with those that had

D) that existed concurrently with other grasshoppers

E) that had existed concurrently with other grasshoppers

A,B,C - Usage of 2 relative modifiers makes the sentence stylistically flawed.
E - usage of past perfect is incorrect as there is no sequencing of two past events.

Hence, D is the Answer.

As per OE,
'Choice C uses a pronoun while D more clearly restates the word grasshoppers, which is both more specific and avoids confusion.'

But 'those' requires a plural antecedent and thus it can't refer to 'grasshopper'
(I also understand that there is an issue with 'that had' in option C)
Even if we remove 'that had' in option C, the option will be incorrect as there is no antecedent for pronoun 'those'

AjiteshArun , GMATNinja , MagooshExpert , GMATGuruNY , VeritasPrepBrian , MartyTargetTestPrep , DmitryFarber , VeritasKarishma , generis , other experts - please enlighten
_________________

I agree that the those is a problem. If we don't use the word grasshoppers, the reader will have to put the right word in there. Definitely not what we'd expect on the GMAT.
_________________

Skywalker18 , first, because I think the phrasing of both
this question and the subsequent answer may create confusion . . .

The specified answer to this question is Option D.

Further, to inform people who may not know about this bit of information:
authors who write SC questions and authors who write SC explanations are not usually
the same authors.

Writing these sentences is incredibly difficult. If it were easy, I suspect that we would have
many more official practice examples than we do.

From any well-respected source, and certainly from Official Guides and Verbal Reviews,
the quality of official explanations can be uneven.*
Sometimes the explanations are excellent.
Sometimes the explanations are less complete or less clear than we might like them to be.

I understand that you are asking about incorrect option C
and in particular about whether "a pronoun [those]" could have a singular antecedent,
a question that AjiteshArun answered.

The author of the OE states that D's use of grasshoppers rather than those "avoids confusion."
Avoiding confusion is one reason that a plural pronoun such as those in option C
may not have a singular antecedent.

The rule about agreement between pronoun and antecedent is not stated, but one basis for the reason is.

I'm glad you highlighted the issue, though, because many readers might decide
that the word "those" refers to the grasshopper species, of which there was more than one member in existence.

*To illustrate the point about the occasional unevenness of OEs with a tiny sample,
in OG 2018, option explanations that consist only of "awkward, wordy, indirect, and confusing"
but that have other errors upon which elimination can be based are:
670D. 674A. 696A. 697C and D. 700E. 712C, D, and E. 724A. 727B, C, and E. 734D. 752E. 754A. 757E. 768A and B. 777E. 778A. 787D. 804D
_________________

Hello from the GMAT Club VerbalBot!

Thanks to another GMAT Club member, I have just discovered this valuable topic, yet it had no discussion for over a year. I am now bumping it up - doing my job. I think you may find it valuable (esp those replies with Kudos).

Want to see all other topics I dig out? Follow me (click follow button on profile). You will receive a summary of all topics I bump in your profile area as well as via email.
_________________