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Scientists claim that the discovery of the first authenticated mammal bones in amber could provide important clues of determining, in addition to how, when mammals colonized the islands of the West Indies.
(A) of determining, in addition to how, when mammals colonized the islands of the West Indies
(B) in the determination of how and when the islands of the West Indies were colonized by mammals
(C) to determine how mammals colonized the islands of the West Indies and when they did
(D) for determining when the islands of the West Indies were colonized by mammals and how they were
(E) for determining how and when mammals colonized the islands of the West Indies
SC61120.02
(A) of determining, in addition to how, when mammals colonized the islands of the West Indies
(B) in the determination of how and when the islands of the West Indies were colonized by mammals
(C) to determine how mammals colonized the islands of the West Indies and when they did
(D) for determining when the islands of the West Indies were colonized by mammals and how they were
(E) for determining how and when mammals colonized the islands of the West Indies
SC61120.02
https://www.nytimes.com/1996/04/16/science/mammal-bones-found-in-amber-for-first-time.html
The discovery of the first authenticated mammal bones in amber was announced in the current issue of the journal Nature by Dr. Ross D. E. MacPhee, a curator of mammalogy at the American Museum of Natural History in New York City, and Dr. David A. Grimaldi, a specialist in amber fossils at the museum.
The scientists said the discovery could provide an important clue to how and when mammals — or any land animals — colonized the islands of the West Indies. Only in recent years have scientists begun to find fossils of vertebrate animals that lived more than a few thousand years ago, long after the islands could have been connected to the mainland as a peninsula accessible to South American land animals.
The discovery of the first authenticated mammal bones in amber was announced in the current issue of the journal Nature by Dr. Ross D. E. MacPhee, a curator of mammalogy at the American Museum of Natural History in New York City, and Dr. David A. Grimaldi, a specialist in amber fossils at the museum.
The scientists said the discovery could provide an important clue to how and when mammals — or any land animals — colonized the islands of the West Indies. Only in recent years have scientists begun to find fossils of vertebrate animals that lived more than a few thousand years ago, long after the islands could have been connected to the mainland as a peninsula accessible to South American land animals.
Besides being incomplete, but more importantly in C and D, what does the pronoun -they - stand for? Is it - the West Indies or the islands or the mammals? - A pronoun should not only stand for its true referent logically but also seem to stand for the due referent unambiguously. So I would rather rule out C and D, notwithstanding other extant errors in these two choices. But E tactfully avoids the pronoun equivocation, uses active voice and employs the right idiom - for determining – and thus is the indisputable choice.
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Posts: 639
Going with E:
A: of determining, in addition to how, when mammals colonized the islands of the West Indies - clues of?(need clues-to or clues-for) WRONG
B:in the determination of how and when the islands of the West Indies were colonized by mammals - clues in? (need clues-to or clues-for).WRONG
C:to determine how mammals colonized the islands of the West Indies and when they did - they is ambiguos. WRONG.
D:for determining when the islands of the West Indies were colonized by mammals and how they were - they is ambiguos. WRONG.
E:for determining how and when mammals colonized the islands of the West Indies - CORRECT.
A: of determining, in addition to how, when mammals colonized the islands of the West Indies - clues of?(need clues-to or clues-for) WRONG
B:in the determination of how and when the islands of the West Indies were colonized by mammals - clues in? (need clues-to or clues-for).WRONG
C:to determine how mammals colonized the islands of the West Indies and when they did - they is ambiguos. WRONG.
D:for determining when the islands of the West Indies were colonized by mammals and how they were - they is ambiguos. WRONG.
E:for determining how and when mammals colonized the islands of the West Indies - CORRECT.
Posts: 6,486
Dear Friends,
Here is a detailed explanation to this question-
Meaning is crucial to solving this problem:
Understanding the intended meaning is key to solving this question; the intended meaning is that the discovery of the first authenticated mammal bones in amber could provide important clues for determining when the islands of the West Indies were colonized by mammals and how the islands were colonized by mammals.
Concepts tested here: Meaning + Pronouns + Verb Forms + Grammatical Construction + Awkwardness/Redundancy
• Information important to the core meaning of the sentence should not be placed between two commas.
• "did so" is used to refer to verbs.
• The infinitive verb form ("to + base form of verb" - "to + determine" in this case) is the preferred construction for referring to the purpose or intent behind an action.
A: This answer choice alters the meaning of the sentence through the phrase "clues of determining"; the construction of this phrase leads to an incoherent meaning; the intended meaning is that the discovery of the first authenticated mammal bones in amber could provide important clues for determining when the islands of the West Indies were colonized by mammals and how the islands were colonized by mammals. Further, Option A incorrectly places information important to the core meaning of the sentence - the fact that the discovery could also provide important clues for determining how mammals colonized the islands of the West Indies - between two commas; remember, information important to the core meaning of the sentence should not be placed between two commas.
B: This answer choice uses the needlessly wordy phrase "in the determination of", leading to awkwardness and redundancy.
C: This answer choice incorrectly uses "did" to refer to the action "colonized the islands of the West Indies"; this usage leads to an incomplete sentence, as in this case, "did" is merely a helping verb, not an active verb; remember, "did so" is used to refer to verbs. Further, Option C alters the meaning of the sentence through the phrase "to determine"; the use of the infinitive verb form ("to + base form of verb" - "to + determine" in this case) incorrectly implies that the discovery could provide clues for the purpose of determining when the islands of the West Indies were colonized by mammals and how the islands were colonized by mammals; the intended meaning is that the discovery could provide clues that could determine when the islands of the West Indies were colonized by mammals and how the islands were colonized by mammals; remember, the infinitive verb form ("to + base form of verb" - "to + determine" in this case) is the preferred construction for referring to the purpose or intent behind an action. Additionally, Option C suffers from pronoun ambiguity, as it is unclear whether "they" refers to "mammals" or "scientists".
D: This answer choice fails to form a complete sentence; here "were" does not form a complete simple past tense verb phrase, rather it is simply part of a simple past tense verb phrase in the passive voice. Further, Option D suffers from pronoun ambiguity, as it is unclear whether "they" refers to "mammals" or "scientists".
E: Correct. This answer choice avoids the verb form error seen in Options D and E, as it acts upon the noun "mammals" with the active verb "colonized" to form a complete thought, leading to a complete sentence. This answer choice uses the phrase "for determining", conveying the intended meaning - that the discovery could provide clues that could determine when the islands of the West Indies were colonized by mammals and how the islands were colonized by mammals. Additionally, Option E avoids the pronoun ambiguity seen in Options C and D, as it uses no pronouns. Option E also avoids the grammatical construction error seen in Option A, as it places no information between commas. Besides, Option E is free of any awkwardness or redundancy.
Hence, E is the best answer choice.
To understand the usage of a pair of commas on GMAT, you may want to watch the following video (~4 minutes):
All the best!
Experts' Global Team
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Here is a detailed explanation to this question-
jerrywu
Meaning is crucial to solving this problem:
Understanding the intended meaning is key to solving this question; the intended meaning is that the discovery of the first authenticated mammal bones in amber could provide important clues for determining when the islands of the West Indies were colonized by mammals and how the islands were colonized by mammals.
Concepts tested here: Meaning + Pronouns + Verb Forms + Grammatical Construction + Awkwardness/Redundancy
• Information important to the core meaning of the sentence should not be placed between two commas.
• "did so" is used to refer to verbs.
• The infinitive verb form ("to + base form of verb" - "to + determine" in this case) is the preferred construction for referring to the purpose or intent behind an action.
A: This answer choice alters the meaning of the sentence through the phrase "clues of determining"; the construction of this phrase leads to an incoherent meaning; the intended meaning is that the discovery of the first authenticated mammal bones in amber could provide important clues for determining when the islands of the West Indies were colonized by mammals and how the islands were colonized by mammals. Further, Option A incorrectly places information important to the core meaning of the sentence - the fact that the discovery could also provide important clues for determining how mammals colonized the islands of the West Indies - between two commas; remember, information important to the core meaning of the sentence should not be placed between two commas.
B: This answer choice uses the needlessly wordy phrase "in the determination of", leading to awkwardness and redundancy.
C: This answer choice incorrectly uses "did" to refer to the action "colonized the islands of the West Indies"; this usage leads to an incomplete sentence, as in this case, "did" is merely a helping verb, not an active verb; remember, "did so" is used to refer to verbs. Further, Option C alters the meaning of the sentence through the phrase "to determine"; the use of the infinitive verb form ("to + base form of verb" - "to + determine" in this case) incorrectly implies that the discovery could provide clues for the purpose of determining when the islands of the West Indies were colonized by mammals and how the islands were colonized by mammals; the intended meaning is that the discovery could provide clues that could determine when the islands of the West Indies were colonized by mammals and how the islands were colonized by mammals; remember, the infinitive verb form ("to + base form of verb" - "to + determine" in this case) is the preferred construction for referring to the purpose or intent behind an action. Additionally, Option C suffers from pronoun ambiguity, as it is unclear whether "they" refers to "mammals" or "scientists".
D: This answer choice fails to form a complete sentence; here "were" does not form a complete simple past tense verb phrase, rather it is simply part of a simple past tense verb phrase in the passive voice. Further, Option D suffers from pronoun ambiguity, as it is unclear whether "they" refers to "mammals" or "scientists".
E: Correct. This answer choice avoids the verb form error seen in Options D and E, as it acts upon the noun "mammals" with the active verb "colonized" to form a complete thought, leading to a complete sentence. This answer choice uses the phrase "for determining", conveying the intended meaning - that the discovery could provide clues that could determine when the islands of the West Indies were colonized by mammals and how the islands were colonized by mammals. Additionally, Option E avoids the pronoun ambiguity seen in Options C and D, as it uses no pronouns. Option E also avoids the grammatical construction error seen in Option A, as it places no information between commas. Besides, Option E is free of any awkwardness or redundancy.
Hence, E is the best answer choice.
To understand the usage of a pair of commas on GMAT, you may want to watch the following video (~4 minutes):
All the best!
Experts' Global Team
_________________
General Discussion
Answer E
In the bold part of the sentence "in addition to" is wordy and inaccurately placed.
The correct phrase is "provide for". This eliminates A, B and C
D - This has so many flaws that please add to the list for I'm sure I'll miss a few. But, to mention a few - usage of passive voice is not preferrable; the way the sentence is worded makes it sounds incomplete/awkward.
E - short and concise; properly connects the "how" and "when"; uses active voice.
In the bold part of the sentence "in addition to" is wordy and inaccurately placed.
The correct phrase is "provide for". This eliminates A, B and C
D - This has so many flaws that please add to the list for I'm sure I'll miss a few. But, to mention a few - usage of passive voice is not preferrable; the way the sentence is worded makes it sounds incomplete/awkward.
E - short and concise; properly connects the "how" and "when"; uses active voice.
Marcab
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Scientists claim that the discovery of the first authenticated mammal bones in amber could provide important clues of determining, in addition to how, when mammals colonized the islands of the West Indies.
A. of determining, in addition to how, when mammals colonized the islands of the West Indies [i]"in addition to how" acts as a modifier and hence it is gievn a low level. Giving equal preference to both HOW and WHEN will correct this option.[/i]
B. in the determination of how and when the islands of the West Indies were colonized by mammals Two mistakes i)"in the determination" is unidiomatic ii)"of" is a preposition and hence it should be followed by a noun or noun phrase
C. to determine how mammals colonized the islands of the West Indies and when they did CLOSE CONTENDER. Reason for elimination- "they" is ambigous
D. for determining when the islands of the West Indies were colonized by mammals and how they were "THEY" is ambigous
E. for determining how and when mammals colonized the islands of the West IndiesCorrect. IMO
Whats the OA and OE.
Whats the source.
IMO E
Hope that helps
-s
A. of determining, in addition to how, when mammals colonized the islands of the West Indies [i]"in addition to how" acts as a modifier and hence it is gievn a low level. Giving equal preference to both HOW and WHEN will correct this option.[/i]
B. in the determination of how and when the islands of the West Indies were colonized by mammals Two mistakes i)"in the determination" is unidiomatic ii)"of" is a preposition and hence it should be followed by a noun or noun phrase
C. to determine how mammals colonized the islands of the West Indies and when they did CLOSE CONTENDER. Reason for elimination- "they" is ambigous
D. for determining when the islands of the West Indies were colonized by mammals and how they were "THEY" is ambigous
E. for determining how and when mammals colonized the islands of the West IndiesCorrect. IMO
Whats the OA and OE.
Whats the source.
IMO E
Hope that helps
-s
is B wrong only because it is not concise?
PrashantPonde
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Schools: Haas EWMBA '17
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Sachin9
"clues in the determination of how" is unnecessarily using the passive voice and its also has awkward construction. Choice (E) is concise and serves the meaning.
PraPon
why is there no rule for awkwardness?
Hi Sachin,
Choice B is incorrect because it is very wordy. It does not have any grammatical error, but it certianly is lot more wordy. Choice E is concise.
Well, there are no rules for awkwardness because it is a stylistic issue and not a grammatical issue.
Hope this helps.
Thanks.
Shraddha
_________________
Choice B is incorrect because it is very wordy. It does not have any grammatical error, but it certianly is lot more wordy. Choice E is concise.
Well, there are no rules for awkwardness because it is a stylistic issue and not a grammatical issue.
Hope this helps.
Thanks.
Shraddha
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PrashantPonde
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Sachin9
Sachin, sometimes you will be able to apply few rules based on grammar or meaning to identify choices with wordy/awkward constructions, however most times you will have to trust your ears to identify such errors. We may "not always" be able to identify/apply the rules for concision.
A quick tip: Always read the SC OG solutions given by GMAC (whether you get the answer right or wrong). Most cases GMAC eliminates answers by just calling them as wordy/awkward (without further explanations), try analyzing those patterns and tune your ears to it. Dont take them as a thumb rule, but during exam once you narrow down to two (grammatically) correct choices, chose the one which is more concise and follows the meaning.
In the concerned problem, "for determining" is more concise (and active in voice) than "in the determination of". Why? check below:
Reasoning & similar example from MGMAT:
Pattern: Prefer verb to action noun
o Wordy: The townspeople’s revolution was against the king.
Revolution is a noun that expresses an action
o Better: The townspeople revolted against the king.
In our case, "determining" verb is preferred over the action noun "(in the) determination of".
Hope this helps.
daagh
Hi Daagh Sir,
WIll you pls suggest why usage of "They" is ambiguous out here ?
As per my understanding They do have clear antecedent as Mammals, especially in C
how mammals colonized the islands of the West Indies and when they did
Garamatically in option C they can refer to Mammals i.e. subject of previous clause. Again these two sentences are parallel and joined by And. SO subject of first sentence is doer of action and same should be doer for "THey did" also.
Pls suggest !
Thanks in advance !
True. I agree. E is preferred more for concision and the use of a more suitable idiom.
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Posts: 57
Hi GMATNinja ,
I have some queries here.
for determining how (mammals colonized the islands of the West Indies) and when mammals colonized the islands of the West Indies .
Is it right to have ellipsis before ?
Thanks
I have some queries here.
Quote:
I think there is no problem with "they" as according to parallelism , "they" must refer to mammals.
Quote:
Is there ellipsis here like :
for determining how (mammals colonized the islands of the West Indies) and when mammals colonized the islands of the West Indies .
Is it right to have ellipsis before ?
Thanks
Posts: 57
Hi,
I have written the queries here for this question.
https://gmatclub.com/forum/scientists-c ... l#p2168633
I have written the queries here for this question.
https://gmatclub.com/forum/scientists-c ... l#p2168633
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guptakashish02
Hi,
I think 'they' can also refer to Scientists as well as per parallelism and 'did' can refer to the action 'Claim'. So , ambiguous and distorts the meaning.
GMATNinja , sir would be great if you can check whether my explanation is correct here.
psaikrishna90
I think that's reasonable, but generally, you want to be careful about relying solely on pronoun ambiguity as a reason to eliminate answer choices. (More on pronoun ambiguity in this video.)
Another problem with (c) is that the construction "AND + Clause" typically introduces a new idea. For example, "Marissa plotted her revenge for several months, and when she finally pounced, her victim was suitably surprised and horrified." Notice that the clause in red introduces a fresh action and consequence.
Similarly, the expectation for a second action makes (C) difficult to understand. It sounds as though we're going to read more information regarding what happened after the mammals colonized the island, and, at best, it's disorienting when we don't get this. Contrast that with (E) in which the parallelism makes it crystal clear what the author is trying to convey - "how" and "when" the mammals colonized the island. Clear and concise beats murky and confusing every time.
I hope that helps!
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daagh
Sir, beside this pronoun ambiguity, isnt there a idiomatic split ? CLUE TO OR CLUE FOR
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Option A – the use of preposition ‘of’ is not idiomatic with the word ‘clue’. Eliminate.
Option B – the use of preposition ‘in’ is not idiomatic with the word ‘clue’. Eliminate.
Option C – the use of pronoun ‘they’ is unclear. Here ‘they’ could refer to West Indies or mammals. Eliminate.
Option D – Same as E. Use of ambiguous pronoun ‘they’. Eliminate.
Option E – clear and concise option.
Option E is the best choice.
Hope this helps!
Option B – the use of preposition ‘in’ is not idiomatic with the word ‘clue’. Eliminate.
Option C – the use of pronoun ‘they’ is unclear. Here ‘they’ could refer to West Indies or mammals. Eliminate.
Option D – Same as E. Use of ambiguous pronoun ‘they’. Eliminate.
Option E – clear and concise option.
Option E is the best choice.
Hope this helps!
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Expert reply
guptakashish02
guptakashish02, good questions.
1) I believe you are correct that "they" is acceptable here, based on the parallel structure. However, when we compare C and E, we notice that E is more concise and clearly communicates the intended meaning with the simple parallel structure "how and when".
2) Yes, this involves ellipsis, but we would normally use "did SO". The OG explanation notes this issue with C.
One more thing that I didn't see discussed above -- this is something I didn't notice when I did the question, but the OG notes a subtle difference between "to determine" vs "for determining":
"To determine (instead of for determining, toward determining, or to help determine) suggests that the clues would be used as a sufficient basis for determining the information needed. That makes it rhetorically somewhat at odds with the standard meaning of clues; clues are normally thought of as incomplete bits of evidence. At the end of the sentence, 'did so' would be more standard and rhetorically effective as an indication that the verb did refers back to colonized the islands of the West Indies."
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