In the past several years, astronomers have detected more than 80 mass

Question

In the past several years, astronomers have detected more than 80 massive planets,  most of them as large or larger than Jupiter, which circle  other stars.

(A) most of them as large or larger than Jupiter, which circle

(B) most of them as large or larger than Jupiter and circling

(C) most of them at least as large as Jupiter, circling

(D) mostly at least as large as Jupiter, which circle

(E) mostly as large or larger than Jupiter, circling

My question is - why is c correct and D wrong? 
The problem i see in c is that the antecedent of "them" is ambiguous. "them" in c can refer to planets or astronomers (isn't it so?)

In D - mostly is an adverb which modifies the adjective (large).

egmat · Accepted Answer

Hi, There is a difference in the meaning between the two sentences cited by you. To understand the same, please have a look at the following sentences: 1. I saw some dogs sitting outside the house. 2. I saw some dogs that sit outside the house. In the first sentence you are talking about those dogs who were sitting outside the house when you spotted them. However, in the second sentence you are talking about a category of dogs and this category of dogs sits outside the house. So, in the second construction you are describing a general feature of these dogs. Do you now see how the description of the planets changes with the change in the construction (from –ing modifier to that clause)?

Thanks, Neeti.

daagh · Answer

The correct route to solve this issue is through the idiom first. Anytime we use  as large , it should be completed by another as –  as large as.  
We can thus eliminate A, B and E; between C and D, we can eliminate D for fouling ‘which’ pronoun touch rule. When there is an eligible noun such as ‘Jupiter’, ‘which’ cannot jump over it and modify the planets

Fistail · Answer

D has 2 flaws:

1. most of them is better than mostly 
2. incorrect modifying phrase that starts with "which" incorrectly refers to Jupitor.

both flaws are corrected in C.

vraptor · Answer

(C)

(A) most of them  as  large or larger than Jupiter, which circle -->  Missing as  
(B) most of them  as  large or larger than Jupiter and circling -->  Missing as  
(C) most of them at least as large as Jupiter, circling --> Correct
(D)  mostly  at least as large as Jupiter, which circle
(E)  mostly  as large or larger than Jupiter, circling

mohnish104 · Answer

If anything, E is a much closer second option than D.

pqhai · Answer

Hello mohnish

Sorry, I have to say E is worse than D! When you see the structure " as + adjective + OR + comparative.... " ==> The correct structure MUST be:  as X as OR larger than....  The second " as " is really important to make a comparison correct.

Hope it helps.

gmatter0913 · Answer

Is there a difference in meaning between the two sentences below?

In the past several years, astronomers have detected more than 80 massive planets circling other stars.
In the past several years, astronomers have detected more than 80 massive planets that circle other stars.

If there is no difference, then would both the sentences below be correct on the GMAT?

In the past several years, astronomers have detected more than 80 massive planets, most of them atleast as large as Jupiter, circling other stars.

In the past several years, astronomers have detected more than 80 massive planets, most of them atleast as large as Jupiter, that circle other stars.

rohan89 · Answer

IMO C

In D the usage of Mostly is incorrect according to me. Also, 'Which' modifies Jupiter. Plus I think Circl ing   is necessary because the action is still going on.

It is easy to chuck other options. Experts, your comments?

Thanks,
Rohan

jaspreets · Answer

Hi Avisek,

Let's understand the intended meaning of this sentence

In the past several years ( is a prepositional phrase that gives more info about time frame)
 
astronomers have detected more than 80 massive planets (this is an independent clause that has a subject astros and verb detected)

,most of them as large or larger than Jupiter, ( this phrase is giving information about planets that is additional and if ignored than you would see - astronomers have detected more than 80 massive planets, which circle other stars.
so now you know that which is a relative pronoun that refers to planets)

An other problem with the sentence is "as large or larger than" that is unidiomatic. The correct usage will be at least as large as .

Thus we can eliminate all answer choices except E and D.

The only difference in E and D is of adjective most. the usage of mostly is incorrect because mostly is an adverb that can't modify the noun planets.

in the end, as i said before " most of them....larger than Jupiter" is an additional phrase which can be omitted then you would see- astronomers have detected more than 80 massive planets,circling other stars. in this sentence circling is modifying the planets.

Hope it helps.

goldfinchmonster · Answer

Guys would be nice if you ppl can put some light on my thought process.

I would go with D.
The reason are 
1) If you omit the  sandwich phrase i.e phrase modifier , option c would sound grammatically incorrect.

..... astronomers have detected more than 80 massive planets, circling other stars.

In case of D, if we eliminate the phrase modifier, then

......... astronomers have detected more than 80 massive planets, which circle other stars.

Even if you eliminate phrase modifier (sandwich phrase) the sentence should make sense. In C it dos't and in D it dose.

2)  Comma ing rule  - I dont know how many of you recognize this rule by this term.

When ever we have a ing form (verb form) of word next to comma, that word should be a effect of a cause described before the comma.

Subject + Verb, ing

Cause , Effect
 Example :- The car stopped, delaying Mike.

Cause Effect 
 Example :- The Bomb Blasted, Killing the man.

Here in option C the first part of the sentence does not signify any cause for the circling to be an effect.

Hope it's clear now.

The answer is D.

prav04 · Answer

In this question, can't 'Them' refer back to Astronomers??

VeritasPrepBrian · Answer

Good question. In my experience, pronoun reference is one of the harder topics for students so I'd heavily advise that you prioritize other decision points before you take a swing at pronoun reference. And it always comes down to this: students who are looking for pronoun reference errors very frequently misdiagnose proper pronoun usage for "hey we don't know what that refers to." The presence of multiple nouns doesn't mean that it's unclear what the pronoun refers to!

Here, note that:

1) "them" exists within a modifier that sits directly adjacent to "planets"

2) "them" describes size (most of them as large as or larger than Jupiter), and "planets" has the adjective "massive" in front of it, lending more credence to the idea that the modifier is expanding on that description of planets

3) "as large as or larger than Jupiter" just couldn't possibly describe people...the size comparison isn't something anyone would ever mistake. Pronoun reference is mostly an issue when you could make the case that the sentence might mislead people (hey, wait - is it the planets or the people who are that massive?) but here there's just no way you could mistake that.

Which...this isn't at all to "shame" anyone who saw pronoun reference as a possible error there. It's hard! Which is why I'd say leverage other, clearer decision points before trying to look for pronoun reference unless the pronoun reference is just plain egregious. If you're actively looking for pronoun reference errors as one of your primary missions, you'll "find" it in a lot of places where it doesn't really exist.

aa008 · Answer

2 commas are placed as parenthesis. 
so the correct answer looks like this.

-In the past several years, astronomers have detected more than 80 massive planets( most of them at least as large as Jupiter) circling other stars.

According to your theory, if you remove  sandwich phrase i.e phrase modifier  sentence would look like

-In the past several years, astronomers have detected more than 80 massive planets circling other stars.

it means there is no comma before  circling

now the rule say, when there is no comma before verb+ing modifier, it modify the preceding noun.

So answer C is in correct.

aniket16c · Answer

Experts can you please explain the use of circling in this question?
So according to my understanding, circling refers to the verb in the previous clause = have detected. And :have detected points to astronomers. 
So have is the use of "circling" justified in this case?

AjiteshArun · Answer

Circling here is a present participle . The pattern here is verb + object + participle , and it is perfectly acceptable. In the past several years, astronomers have detected more than 80 massive planets, most of them at least as large as Jupiter, circling other stars. Ignore the most of them at least as large as Jupiter bit. Circling is not meant to be read as a comma + ing here! Astronomers have detected more than 80 massive planets circling other stars. and not Astronomers have detected more than 80 massive planets , circling other stars. Once we understand that we're not dealing with a comma + ing, some of the rules you're trying to apply won't actually work here. Let's start with what circling is "pointing to". It is pointing to planets , not have detected . If it were pointing to have detected, it'd tell us what the astronomers were doing when they detected the planets.

The sentence in the question could be read (roughly) as Astronomers have detected more than 80 massive planets as they (the planets) were circling other stars. This is like saying I saw you driving a car . ≈ "I saw you as you were performing the action of driving a car". The subject of this sentence is I and the verb is saw (not driving ).

Vaibhavde · Answer

Hi  daagh

About the ‘which’ pronoun touch rule- 
'From the bark of the paper birch tree the Menomini crafted a canoe about twenty feet long and two feet wide, with small ribs and rails of cedar, which could carry four persons or eight hundred pounds of baggage yet was so light that a person could easily portage it around impeding rapids.'

How come which jumped over 'Cedar' to 'Canoe' in this particular sentence from the Official guide?
I've read through all the comments but it still confuses me. Would appreciate if you could clarify.

daagh · Answer

Relative pronoun touch rule does not mean that the relative pronoun has to always refer to the noun that is in front. This rule is subject to rational and sensible appropriateness of the noun before. Most often, and especially in higher-level questions of SC, the relative pronoun does not refer to the noun before. The idea of this ploy by GMAT is to see whether the student is just mechanical or focussed on the communication essentials.

This is the reason for the confusion in this given case also. 
It does not take much to decide that neither the cedar( a plant) nor the ribs nor the rails could carry eight hundred pounds. It is the canoe. Would anyone, therefore, find fault with an official question, and what can then be the real answer?

We must be adaptable and go by larger wisdom when we are dealing with alien languages.

The Takeaway --Logic is the Supreme court in deciding the antecedence of relative pronouns.

svasan05 · Answer

In the past several years, astronomers have detected more than 80 massive planets,  most of them as large or larger than Jupiter, which circle  other stars.

(A) most of them as large or larger than Jupiter, which circle  The correct usage is "as large  as ". Eliminate.

(B) most of them as large or larger than Jupiter and circling  Same error as in (A). Eliminate.

(C) most of them at least as large as Jupiter, circling  Correct answer - idiom error is rectified and no new errors are introduced.

(D) mostly at least as large as Jupiter, which circle  Incorrect usage of adverb "mostly" to modify noun "planets". Eliminate.

(E) mostly as large or larger than Jupiter, circling  Same errors as in (D) and (A). Eliminate.

Hope this helps.

750Barrier · Answer

the answer is C -that is correct- but in E, 'which' does not refer to jupiter. because the verb 'circle' is plural.

In the past several years, astronomers have detected more than 80 mass

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GMAT Sentence Correction (SC - EA only) Questions

In the past several years, astronomers have detected more than 80 mass

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