GMAT Question of the Day - Daily to your Mailbox; hard ones only

It is currently 22 Oct 2019, 14:34

Close

GMAT Club Daily Prep

Thank you for using the timer - this advanced tool can estimate your performance and suggest more practice questions. We have subscribed you to Daily Prep Questions via email.

Customized
for You

we will pick new questions that match your level based on your Timer History

Track
Your Progress

every week, we’ll send you an estimated GMAT score based on your performance

Practice
Pays

we will pick new questions that match your level based on your Timer History

Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.

Close

Request Expert Reply

Confirm Cancel

Recently physicians have determined that stomach ulcers are not caused

  new topic post reply Question banks Downloads My Bookmarks Reviews Important topics  
Author Message
TAGS:

Hide Tags

Find Similar Topics 
VP
VP
User avatar
V
Joined: 23 Feb 2015
Posts: 1265
GMAT ToolKit User Premium Member
Re: Recently physicians have determined that stomach ulcers are not caused  [#permalink]

Show Tags

New post 28 Jan 2019, 02:37
1
Hi EMPOWERgmatVerbal,
Thank you for this broad explanation of this question. Can I add choice F as possible correct choice?
Thanks__

Quote:
Recently physicians have determined that stomach ulcers are not caused by stress, alcohol, or rich foods, but a bacterium that dwells in the mucous lining of the stomach.

A. not caused by stress, alcohol, or rich foods, but
B. not caused by stress, alcohol, or rich foods, but are by
C. caused not by stress, alcohol, or rich foods, but by
D. caused not by stress, alcohol, and rich foods, but
E. caused not by stress, alcohol, and rich foods, but are by

Possible Choice F:
F) Recently physicians have determined that stomach ulcers are caused not by stress, alcohol, and rich foods, but by a bacterium that dwells in the mucous lining of the stomach.
EMPOWERgmatVerbal wrote:
Hello Everyone!

This is a great example of a sentence that focuses on parallelism, so let's dive in! To start, let's take a quick look at the original question, and highlight the main differences in orange:

Recently physicians have determined that stomach ulcers are not caused by stress, alcohol, or rich foods, but a bacterium that dwells in the mucous lining of the stomach.

A. not caused by stress, alcohol, or rich foods, but
B. not caused by stress, alcohol, or rich foods, but are by
C. caused not by stress, alcohol, or rich foods, but by
D. caused not by stress, alcohol, and rich foods, but
E. caused not by stress, alcohol, and rich foods, but are by

After a quick glance over the options, there are a few things we can focus on:

1. not caused / caused not (parallelism/idioms)
2. or / and (meaning/lists)
3. but / but are by / but by (parallelism/idioms)


Since we know this question mainly focuses on parallelism, let's tackle #1 & #3 on our list at the same time. This is the idiom structure we're working with here:

not X, but Y

Both X and Y must be written using parallel structure, including word placement, verb tenses, singular/plural, etc. Since the phrase "caused by" is included in this sentence, we need to be careful to make sure it's included in both X and Y only if it appears after the word "not:"

not caused by X, but caused by Y = PARALLEL
not caused by X, but Y = NOT PARALLEL

caused not by X, but by Y = PARALLEL
caused not by X, but caused by Y = NOT PARALLEL
caused not by X, but Y = NOT PARALLEL

Let's add in the end of the sentence to see which options use parallel structure, and eliminate those that don't:

A. not caused by stress, alcohol, or rich foods, but a bacterium that dwells in the mucous lining of the stomach. --> not caused by X, but Y = NOT PARALLEL
B. not caused by stress, alcohol, or rich foods, but are by a bacterium that dwells in the mucous lining of the stomach. --> not caused by X, but are by Y = NOT PARALLEL
C. caused not by stress, alcohol, or rich foods, but by a bacterium that dwells in the mucous lining of the stomach. --> caused not by X, but by Y = PARALLEL
D. caused not by stress, alcohol, and rich foods, but a bacterium that dwells in the mucous lining of the stomach. --> caused not by X, but Y = NOT PARALLEL
E. caused not by stress, alcohol, and rich foods, but are by a bacterium that dwells in the mucous lining of the stomach. --> caused not by X, but are by Y = NOT PARALLEL

There you have it! Option C is correct because it's the only one that uses parallel structure within the idiom "not X, but Y." By focusing on parallelism, you should be able to answer this question pretty quickly!


Don't study for the GMAT. Train for it.

_________________
“The heights by great men reached and kept were not attained in sudden flight but, they while their companions slept, they were toiling upwards in the night.”
Henry Wadsworth Longfellow

Do you need official questions for Quant?
3700 Unique Official GMAT Quant Questions
------
SEARCH FOR ALL TAGS
GMAT Club Tests
VP
VP
User avatar
V
Joined: 23 Feb 2015
Posts: 1265
GMAT ToolKit User Premium Member
Re: Recently physicians have determined that stomach ulcers are not caused  [#permalink]

Show Tags

New post 28 Jan 2019, 03:16
Hi my honorable expert MartyMurray, DmitryFarber, ccooley, GMATNinja.
I'll be very glad if I've your feedback for this confusing choice B.

Quote:
Recently physicians have determined that stomach ulcers are not caused by stress, alcohol, or rich foods, but a bacterium that dwells in the mucous lining of the stomach.
A. not caused by stress, alcohol, or rich foods, but
B. not caused by stress, alcohol, or rich foods, but are by
C. caused not by stress, alcohol, or rich foods, but by
D. caused not by stress, alcohol, and rich foods, but
E. caused not by stress, alcohol, and rich foods, but are by


The question is totally Parallelism issue. Here the correct answer is C. But, my question is: WHY not B. B makes parallelism to me!
B. NOT (tag)+CAUSED (verb)+by+something....................BUT (tag)+ARE (verb)+by+Something
Indicate parallelism to each other!!
Thanks...
_________________
“The heights by great men reached and kept were not attained in sudden flight but, they while their companions slept, they were toiling upwards in the night.”
Henry Wadsworth Longfellow

Do you need official questions for Quant?
3700 Unique Official GMAT Quant Questions
------
SEARCH FOR ALL TAGS
GMAT Club Tests
Manhattan Prep Instructor
User avatar
S
Joined: 22 Mar 2011
Posts: 1563
Re: Recently physicians have determined that stomach ulcers are not caused  [#permalink]

Show Tags

New post 28 Jan 2019, 17:42
The problem is that "are by" doesn't mean anything here. Notice that we already have the verb "are," so one way to read B would be "are not (caused by X) but are are by y." Another way to think about it is that "caused" isn't really a verb here--it's a past participle. It describes where stomach ulcers come from, not what they do. Making it parallel to a simple verb ("are") doesn't work.

If we don't want to put "caused" before the first parallel marker ("not"), as in C, then we need it after each marker: NOT caused by x BUT caused by y. However, in this case there's no reason to use that longer form. C solves the problem much more elegantly.
_________________

Dmitry Farber | Manhattan Prep GMAT Instructor | San Diego


Manhattan GMAT Discount | Manhattan GMAT Course Reviews | View Instructor Profile |
Manhattan GMAT Reviews
VP
VP
User avatar
V
Joined: 23 Feb 2015
Posts: 1265
GMAT ToolKit User Premium Member
Re: Recently physicians have determined that stomach ulcers are not caused  [#permalink]

Show Tags

New post 28 Jan 2019, 18:40
DmitryFarber wrote:
The problem is that "are by" doesn't mean anything here. Notice that we already have the verb "are," so one way to read B would be "are not (caused by X) but are are by y." Another way to think about it is that "caused" isn't really a verb here--it's a past participle. It describes where stomach ulcers come from, not what they do. Making it parallel to a simple verb ("are") doesn't work.

If we don't want to put "caused" before the first parallel marker ("not"), as in C, then we need it after each marker: NOT caused by x BUT caused by y. However, in this case there's no reason to use that longer form. C solves the problem much more elegantly.

My ultimate query is to fix B like your highlighted part. Now, it make sense to me. Many many thanks DmitryFarber!

Also, one more query:
Can I add choice F as possible correct choice?
Thanks__

Quote:
Recently physicians have determined that stomach ulcers are not caused by stress, alcohol, or rich foods, but a bacterium that dwells in the mucous lining of the stomach.

A. not caused by stress, alcohol, or rich foods, but
B. not caused by stress, alcohol, or rich foods, but are by
C. caused not by stress, alcohol, or rich foods, but by
D. caused not by stress, alcohol, and rich foods, but
E. caused not by stress, alcohol, and rich foods, but are by

Possible Choice F:
F) Recently physicians have determined that stomach ulcers are caused not by stress, alcohol, and rich foods, but by a bacterium that dwells in the mucous lining of the stomach
_________________
“The heights by great men reached and kept were not attained in sudden flight but, they while their companions slept, they were toiling upwards in the night.”
Henry Wadsworth Longfellow

Do you need official questions for Quant?
3700 Unique Official GMAT Quant Questions
------
SEARCH FOR ALL TAGS
GMAT Club Tests
Manhattan Prep Instructor
User avatar
S
Joined: 22 Mar 2011
Posts: 1563
Re: Recently physicians have determined that stomach ulcers are not caused  [#permalink]

Show Tags

New post 29 Jan 2019, 00:02
Normally, we don't use "and" with lists of negatives, because it's then unclear whether we mean to negate each of the items, or just all of them together as a group. In other words, if I say "I don't have a car and a bicycle," now you don't know whether I have just one of those things or neither of them. If I say "Ulcers are not caused by X, Y, and Z," I seem to be saying that the combination of XYZ does not cause ulcers, whereas I think the intent here is to say that none of those things cause ulcers at all.
_________________

Dmitry Farber | Manhattan Prep GMAT Instructor | San Diego


Manhattan GMAT Discount | Manhattan GMAT Course Reviews | View Instructor Profile |
Manhattan GMAT Reviews
Intern
Intern
avatar
B
Joined: 04 Jun 2018
Posts: 24
Location: Viet Nam
Concentration: International Business, Operations
GMAT 1: 610 Q47 V27
GMAT 2: 620 Q46 V29
WE: Supply Chain Management (Internet and New Media)
GMAT ToolKit User
Re: Recently physicians have determined that stomach ulcers are not caused  [#permalink]

Show Tags

New post 02 May 2019, 02:11
Hi Experts,

Are there any differences in sentence meaning between "ulcers are not caused by X but by Y" and "ulcers are caused not by X but by Y"?

TIA!
Manhattan Prep Instructor
User avatar
S
Joined: 22 Mar 2011
Posts: 1563
Recently physicians have determined that stomach ulcers are not caused  [#permalink]

Show Tags

New post 04 May 2019, 22:10
2
lybeaver The first version doesn't work. If we use the form "not . . . but," it creates a parallel structure. Whatever follows "not" has to match what follows "but." As long as we make our terms parallel, we can contrast as much or as little of a phrase as we want. Consider the following three options, all of which work grammatically, at least in theory:

Ulcers are NOT caused by x BUT caused by y.
Ulcers are caused NOT by x BUT by y. (This form probably strikes the best balance for this particular statement.)
Ulcers are caused by NOT x BUT y. (This doesn't work well, but keep reading.)

Most folks would find the first overly wordy, but it's not wrong, and this kind of form is quite common if the two verbs are different. For instance, we might say "Most great poems are NOT created in a flash inspiration BUT RATHER crafted painstakingly through many hours of revision."

The last form (with just x and y as parallel terms) would probably not fly on the GMAT, simply because "by not x" sounds confusing. It almost seems like we're saying that "not x" caused something. Why do that when we can fix the problem by putting "by" after "not"? However, look at this usage: "I was visited by not one but three members of the team." This makes sense, since "not one but three" is basically just a way to emphasize that three is a large number in this context. While it wouldn't be wrong to say "I was visited not by one but by three members of the team," but it doesn't create the same emphasis.

So, long story short? Start by making sure that whenever we have closed markers (not only/but also, either/or, etc.), the words/phrases after each marker match precisely. Typically, we want the exact same part of speech, although we might have, for instance, a noun in one case and a modified noun in the other. ("I want not only a cookie but also a warm blanket.") Don't automatically cut a choice for repeating too much (e.g. "not caused by X but caused by Y") unless the repetition creates an error. Then, look to make sure that the complete structure works to convey the intended meaning.
_________________

Dmitry Farber | Manhattan Prep GMAT Instructor | San Diego


Manhattan GMAT Discount | Manhattan GMAT Course Reviews | View Instructor Profile |
Manhattan GMAT Reviews
Manager
Manager
User avatar
B
Joined: 24 Sep 2018
Posts: 99
Location: India
Re: Recently physicians have determined that stomach ulcers are not caused  [#permalink]

Show Tags

New post 12 Jul 2019, 00:42
Recently physicians have determined that stomach ulcers are not caused by stress, alcohol, or rich foods, but a bacterium that dwells in the mucous lining of the stomach.


(A) not caused by stress, alcohol, or rich foods, but

(B) not caused by stress, alcohol, or rich foods, but are by

(C) caused not by stress, alcohol, or rich foods, but by

(D) caused not by stress, alcohol, and rich foods, but

(E) caused not by stress, alcohol, and rich foods, but are by


NOT BY "X" BUT BY "Y" IS THE CORRECT PHRASE. SO C IS THE ANSWER
_________________
Thanks,
Bijaya

If this post is helpful for you please press the kudos button
Manager
Manager
avatar
B
Joined: 23 Oct 2018
Posts: 51
Re: Recently physicians have determined that stomach ulcers are not caused  [#permalink]

Show Tags

New post 02 Aug 2019, 01:23
+1 for C

caused not by stress, alcohol, or rich foods, but by- maintains parallelism (not by....but by)
GMAT Club Bot
Re: Recently physicians have determined that stomach ulcers are not caused   [#permalink] 02 Aug 2019, 01:23

Go to page   Previous    1   2   [ 29 posts ] 

Display posts from previous: Sort by

Recently physicians have determined that stomach ulcers are not caused

  new topic post reply Question banks Downloads My Bookmarks Reviews Important topics  





Powered by phpBB © phpBB Group | Emoji artwork provided by EmojiOne