Unlike frogs that metamorphose from tadpoles into adults within a one-

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 core meaning of this sentence is that the mountain yellow-legged frogs of the Sierra Nevada reach adulthood in three to four years, so they are restricted to deeper bodies of water that do not dry up in summer or freeze solid in winter.

Concepts tested here: Meaning + Modifiers + Comparison + Pronouns

• In the “phrase + comma + noun” and “noun + comma + phrase” constructions, the phrase must correctly modify the noun; this is one of the most frequently tested concepts on GMAT sentence correction.
• A pronoun can only have one referent in a sentence.
• A comparison must always be made between similar elements.

A: This answer choice incorrectly compares "frogs that metamorphose from tadpoles into adults within a one-year period" to the placeholder pronoun "it"; remember, a comparison can only be made between similar things.

B: This answer choice incorrectly compares "frogs that metamorphose from tadpoles into adults within a one-year period" to the placeholder pronoun "it"; remember, a comparison can only be made between similar things. Further, Option B incorrectly uses "it" both as a placeholder pronoun and to refer to the noun phrase "the mountain yellow-legged frog of the Sierra Nevada"; remember, a pronoun can only have one referent in a sentence. Additionally, Option B alters the meaning of the sentence through the phrase "takes...three to four years until it reaches adulthood"; the construction of this phrase leads to an incoherent meaning; the intended meaning is that the mountain yellow-legged frogs of the Sierra Nevada reach adulthood in three to four years.

C: This answer choice incorrectly uses "in the Sierra Nevada" to modify "mountain yellow-legged tree frogs", incorrectly implying that mountain yellow-legged tree frogs reach adulthood in three to four years if they are in the Sierra Nevada; the intended meaning is that the mountain yellow-legged tree frogs native to the Sierra Nevada reach adulthood in three to four years; remember, in a “phrase + comma + noun” construction, the phrase must correctly modify the noun.

D: This answer choice alters the meaning of the sentence through the phrase "take three to four years until they reach adulthood"; the construction of this phrase leads to an incoherent meaning; the intended meaning is that the mountain yellow-legged frogs of the Sierra Nevada reach adulthood in three to four years. Further, Option D incorrectly modifies "adulthood" with "thus restricted to deeper bodies of water...winter", illogically implying that the adulthood of the frogs was restricted to deeper bodies of water that do not dry up in summer or freeze solid in winter; the intended meaning is that the frogs themselves are restricted to deeper bodies of water that do not dry up in summer or freeze solid in winter; remember, in a “noun + comma + phrase” construction, the phrase must correctly modify the noun.

E: Correct. This answer choice uses the phrase "take three to four years to reach adulthood" and avoids the modifier error seen in Option C, as it uses the phrase "mountain yellow-legged frogs of the Sierra Nevada", conveying the intended meaning - that the mountain yellow-legged tree frogs native to the Sierra Nevada reach adulthood in three to four years. Moreover, Option E avoids the modifier error seen in Option D, as it uses the phrase "and so they are restricted to deeper bodies of water...winter", conveying the intended meaning - that "they" - the frogs themselves - are restricted to deeper bodies of water that do not dry up in summer or freeze solid in winter. Further, Option E avoids the pronoun error seen in Option B, as it uses the pronoun "they" to refer to only one referent - "mountain yellow-legged frogs of the Sierra Nevada". Additionally, Option E correctly compares "frogs that metamorphose from tadpoles into adults within a one-year period" with "mountain yellow-legged frogs of the Sierra Nevada".

Hence, E is the best answer choice.

To understand the concept of "Phrase Comma Subject" and "Subject Comma Phrase" on GMAT, you may want to watch the following video (~1minute):



All the best!
Experts' Global Team

Usage of "until" is wrong here.

what follows "until" is the condition when the action before "until" stops.

Eg. I will keep walking until I see a pond.

E, it is.
Unlike like like should be used to compare nouns. So A,B,C are out
D take three to four years until; (usage of until- take three to four years for what)
E Idiomatically correct to reach adulthood, they clearly refers to the frogs (yellow-legged)

I didn't see the idiom at all. Basing my decision on meaning

In D there is a suddenly shift after comma with thus doesn't have much sense. Moreover, the frogs and they in the same sentence is redundant; we already have a subject clear and straight.

In E: unlike X, Y do something or have certain characteristics , AND they are incapsulated in something I do not know whatever else who cares...........

Really nice question +1

Regards

I would keep myself away getting into nitty gritty of the sentences, especially, when I have more sound reasoning present.

In D, what does phrase modify "restricted to deeper....." --> Modifies "Adulthood" --> Incorrect.

Moreover, sentence is trying to get into Cause Effect phenomenon. E clearly sets this in.

It refers unambiguously to yello legged frogs.
Here is the rule:
Subject pronoun in one clause refers to the subject of another clause.

Example:
Petrol cars have huge maintenance, and hence they are unaccepted in poor countries.
Here they refers to petrol cars.

In the original sentence, unlike x is just a modifier.. Real sentence starts after modifier.
Let me know in case of any doubt
Regards
Imhimanshu

Posted from my mobile device

Boils down to (D) and we when we remember the below construction:

Unlike X,Y

X || Y

Why I rejected (D) is some other reason than given by previous posters.

It should have been

,thus are restricted...

Or

; thus an independent clause.

Both are missing. Hence , incorrect!

Comparison problem.

Unlike frogs that metamorphose from tadpoles into adults within a one-year period, it takes three to four years for the mountain yellow-legged frog of the Sierra Nevada to reach adulthood, and so they are restricted to deeper bodies of water that do not dry up in summer or freeze solid in winter.

(A) it takes three to four years for the mountain yellow-legged frog of the Sierra Nevada to reach adulthood, and so they are --Unlike frog...it takes.. improper comparison
(B) it takes the mountain yellow-legged frog of the Sierra Nevada three to four years until it reaches adulthood, and therefore it is--Unlike frog...it takes.. improper comparison
(C) in the Sierra Nevada, mountain yellow-legged tree frogs take three to four years to reach adulthood, thus being--Unlike frog...in the Sierra Nevada.. improper comparison(D) mountain yellow-legged frogs of the Sierra Nevada take three to four years until they reach adulthood, thus--There is no conjunction. There is no verb after THUS.
(E) mountain yellow-legged frogs of the Sierra Nevada take three to four years to reach adulthood, and so they are--AND is used to join the independent clause which has a working verb ARE. CORRECT

pqhai carcass sayantanc2k

Faced the same question in one of the GMAT prep test, but with a slight variation.

You can see the difference in the clause after the comma in Option E, any views how "with the result" is correct?

I generally found sentences/clauses starting "with" to be a bit awkward, any help please..

Hi Pqhai,

Can you please explain why C is wrong?

I think the subject of choice is mountain yellow-legged tree frog, which is a logical comparison with frogs.

Thx for your time in advance.

bubblehead0922, there are a few issues with (C). First, you're right that "mountain yellow-legged tree frogs" would be a perfectly good comparison, but the trouble is that the phrase "in the Sierra Nevada" is in the way. So now we've broken the "unlike X, Y" structure: "Unlike frogs that metamorphose from tadpoles into adults within a one-year period, in the Sierra Nevada..." That construction isn't anywhere near as clear as the construction in (D) or (E).

"Being" is also a problem. I'm not quite sure what "being" is trying to do here -- I guess it's trying to modify the frogs? And "being" can't be used as a modifier on the GMAT -- only as a noun or a verb. There's a discussion of "being" on one of the QOTD threads if you're curious for more: https://gmatclub.com/forum/qotd-heavy-c ... 40146.html

I hope this helps!

Dear GMATNinja,

Thx for your explanation.

1. Can you please confirm that "Unlike X, Y" structure can never be interrupted in GMAT, as Choice C does?
2. Can "being restricted" function as a passive version of verb-ing modifier? It means the frog is restricted to deeper bodies of water,because it took 3 to 4 years to reach adulthood.
3. Do you think the change of the placement of "Sierra Nevada" alter the intended meaning of the original sentence?

Can anyone explain why D is wrong?

1. The "(un)like X, Y" structure can be interrupted, but you'd need to have a really good reason for doing so. The only case I've ever seen in a correct SC sentence would involve a noun modifier: "Unlike United Airlines, which is apparently run by buffoons, Southwest Airlines believes that passengers are actually human." That noun modifier between the two airlines doesn't hurt the clarity of the comparison at all, so you occasionally see this type of construction on the GMAT. The placement of "in the Sierra Nevada" in choice (C) definitely hurts the clarity of the comparison.

2. Passive voice is a characteristic of verb phrases -- so it doesn't make sense to talk about a modifier as "passive." And I don't think that "being" is never used as a modifier on the GMAT. (For more on passive voice, there's a brief discussion here: https://gmatclub.com/forum/active-vs-pa ... 74613.html. Also a short discussion of "being" in last Wednesday's chat transcript: https://gmatclub.com/forum/verbal-chat- ... l#p1853539.)

3. I guess it does a little bit. In (D) and (E), the frogs' location is an inherent part of how you describe the animal ("frogs of the Sierra Nevada"); in (C), it just sounds like the frogs take a few years to reach adulthood only when they happen to be in the Sierra Nevada. So (D) and (E) are a little bit better in terms of meaning, too.

Unlike frogs that metamorphose from tadpoles into adults within a one-year period, it takes three to four years for the mountain yellow-legged frog of the Sierra Nevada to reach adulthood, and so they are restricted to deeper bodies of water that do not dry up in summer or freeze solid in winter.

(A) it takes three to four years for the mountain yellow-legged frog of the Sierra Nevada to reach adulthood, and so they are
(B) it takes the mountain yellow-legged frog of the Sierra Nevada three to four years until it reaches adulthood, and therefore it is
(C) in the Sierra Nevada, mountain yellow-legged tree frogs take three to four years to reach adulthood, thus being
(D) mountain yellow-legged frogs of the Sierra Nevada take three to four years until they reach adulthood, thus
(E) mountain yellow-legged frogs of the Sierra Nevada take three to four years to reach adulthood, with the result that they are

Edited question from GMATPrep Exam Pack 1 [LINK]

Unlike frogs that metamorphose from tadpoles into adults within a one-year period, it takes three to four years for the mountain yellow-legged frog of the Sierra Nevada to reach adulthood, and so they are restricted to deeper bodies of water that do not dry up in summer or freeze solid in winter.

(A) it takes three to four years for the mountain yellow-legged frog of the Sierra Nevada to reach adulthood, and so they are
(B) it takes the mountain yellow-legged frog of the Sierra Nevada three to four years until it reaches adulthood, and therefore it is
(C) in the Sierra Nevada, mountain yellow-legged tree frogs take three to four years to reach adulthood, thus being
(D) mountain yellow-legged frogs of the Sierra Nevada take three to four years until they reach adulthood, thus
(E) mountain yellow-legged frogs of the Sierra Nevada take three to four years to reach adulthood, with the result that they are

GMATNinjaTwo Could you help to explain the phrase "with the result that" in (E)? Does "comma, with" modify the whole preceding clause?

Similar sentence from GMATPREP. [LINK]

Hasn't this question already been thoroughly beaten to death here? https://gmatclub.com/forum/unlike-frogs ... 51036.html


In choice (E), the clause introduced by "with the result that" modifies the verb "take". For example, "I ate, with the result that I was full." To what extent did I eat? To the extent that I was full.

In the park example, the prepositional phrase, "with arms and legs..." functions as an adverb modifying "sleeping". How were the monkeys sleeping? With arms and legs hanging...