Industrialization and modern methods of insect control have improved

Question

Industrialization and modern methods of insect control have improved the standard of living around the globe  while at the same time they have introduced some 100,000 dangerous chemical pollutants, having  gone virtually unregulated since they were developed more than 50 years ago.

(A) while at the same time they have introduced some 100,000 dangerous chemical pollutants, having

(B) while at the same time introducing some 100,000 dangerous chemical pollutants that have

(C) while they have introduced some 100,000 dangerous chemical pollutants at the same time, which have

(D) but introducing some 100,000 dangerous chemical pollutants at the same time that have

(E) but at the same time introducing some 100,000 dangerous chemical pollutants, having

https://www.nytimes.com/2000/11/28/science/negotiators-focus-on-dirty-dozen-pollutants.html

Industrialization and modern insect control have improved the quality of life around the globe,  but they have also added some 100,000 chemical compounds that , some scientists worry, could affect the health of people and wildlife. These persistent organic pollutants, known as POP's,  have  gone virtually unregulated since they were developed more than 50 years ago.

daagh · Accepted Answer

kivalo wrote

Apart from its usage as a conjunction with a finite verb, 'while' is also used along with participles. GMAT has accepted this usage also, as can be seen below. Therefore, one cannot omit a choice on this count.

1. The themes that Rita Dove explores in her poetry  is universal, encompassing much of the human condition while occasionally she deals  with racial issues. 
A. is universal, encompassing much of the human condition while occasionally she deals
B. is universal, encompassing much of the human condition, also occasionally it deals
C. are universal, they encompass much of the human condition and occasionally deals
D. are universal, encompassing much of the human condition  while occasionally dealing 
E. are universal, they encompass much of the human condition, also occasionally are dealing

OA D

2.  While studying the genetic makeup  of corn, a new class of mutant genes was discovered by Barbara McClintock, a discovery which led to greater understanding of cell differentiation.

A. a new class of mutant genes was discovered by Barbara McClintock, a discovery which led
B. a new class of mutant genes in corn were discovered by Barbara McClintock, leading
C. Barbara McClintock discovered a new class of mutant genes, and it led
D. Barbara McClintock discovered a new class of mutant genes, a discovery that led
E. Barbara McClintock, who discovered a new class of mutant genes, leading

The non-underline part uses while along with a participle

3. Meteor showers and individual streaks of light that flash across the sky every night are generated when tiny flecks of celestial detritus, often no larger than grains of sand or of pebbles, burn up speeding through the atmosphere.

(A) grains of sand or of pebbles, burn up speeding 
(B) grains of sand or pebbles, burn up  while speeding  
(C) grains of sand or pebbles, which burn up while speeding 
(D) a grain of sand or pebble, which burns up as it speeds 
(E) a grain of sand or a pebble burns up when it speeds

OA.B

prasun9 · Answer

A. while at the same time they have introduced some 100,000 dangerous chemical pollutants,  having   -  Having gone virtually unregulated  introduces a cause-effect scenario, but there is no such cause and effect relationship here. E.g. He felt sick, having eaten too much. 
B. while at the same time introducing some 100,000 dangerous chemical pollutants that have  - This is grammatically correct. The Simple Present  introducing  is used here in order to show that the pollutants can still be introduced. The methods in question are not done introducing pollutants, they are still capable of introducing pollutants. 
C. while they have introduced some 100,000 dangerous chemical pollutants  at the same time ,  which  have  - Changes the meaning by misplacing "at the same time". Also "which" incorrectly modifies time instead of pollutants 
D. but introducing some 100,000 dangerous chemical pollutants  at the same time  that have  - Changes the meaning like C because of the placement of "at the same time" 
E. but at the same time introducing some 100,000 dangerous chemical pollutants,  having   - Having introduces an incorrect cause-effect scenario, just as A

sayantanc2k · Answer

"Introducing" is a present participle, not a verb. Since this is an official question, it is clear that GMAT allows usage of "while" to introduce a present participle phrase.
(It is important to align oneself with what GMAT considers right or wrong - scoring high is after all the objective.)

GMATNinja · Answer

The problem with (A) is the logic. Anytime we have CLAUSE + COMMA + VERB-ING, the verb-ing modifier will describe the previous clause and provide additional information about the action performed in that clause. For example, "Amy decided not to attend any more Phish concerts in 2018, having already gone to so many that she she'd begun to lose contact with reality." "Having already gone..." gives us additional information about the previous clause, shedding light on  why  Amy decided not to go to more Phish concerts. It's important to note here that because Amy is the subject of the previous clause, "having already gone" is describing  her .

Now look at the relevant portion of (A), "they have introduced some 100,000 dangerous chemical pollutants, having gone virtually unregulated since they were developed more than 50 years ago.." In this case, "having gone unregulated" seems to be describing the subject of the previous clause, "they." "They" refers to "modern methods." But it's not the "modern methods" that have gone unregulated - it's the chemical pollutants. How could  modern  methods have gone unregulated for 50 years? So while (A) might not have a definitive grammatical problem, its meaning is illogical.

I hope that helps!

vishwaprakash · Answer

POE

A. while at the same time they have introduced some 100,000 dangerous chemical pollutants, having
Incorrect - Ambiguous modifier ", Having" it has potential to modify pollutants and They (Industrialization and modern methods of insect control) Hence sentence is not clear to present an Idea.

B. while at the same time introducing some 100,000 dangerous chemical pollutants that have
Correct 
1. introducing - Ving modifier modifies the subject of preceding clause ( Industrialization and modern methods of insect control) 
2. That - correct modify Pollutants.

C. while they have introduced some 100,000 dangerous chemical pollutants at the same time, which have
Incorrect - 
1. Change of Meaning (Sin in GMAT SC) , 
Original Meaning - "At the same time, they have introduced 100,000 pollutants"
Meaning in option - "They have introduced 100,000 pollutant at the same time.

2. "Time, which" - which is modifying the time, Time modifier is when. Even tough Which modifies time, it introduced change in meaning by saying " Time gone viral .. "

D. but introducing some 100,000 dangerous chemical pollutants at the same time that have
Incorrect - Here But introduced an Independent clause and has no verb in it.
E. but at the same time introducing some 100,000 dangerous chemical pollutants, having
Incorrect - Here But introduced an Independent clause and has no verb in it.

GMATNinja · Answer

Sure, "while" can mean "at the same time", but it can also mean "although." I honestly don't love the use of "while at the same time" because it feels a little bit redundant to me, but it's not wrong. You could easily argue that "at the same time" helps clarify the meaning. At the very least, you wouldn't want to eliminate anything based on that issue alone.

Yup, you have the right idea. "Having + verb" will generally be the first of two actions. I didn't emphasize that in  my post above , because it's also try that "having + verb" needs to logically modify the preceding (or subsequent) clause. And you're correct that your two sentences about Samiya are basically are the same meaning-wise, though we might argue that it's a little bit cleaner to start with the first action ("having studied for two hours").

You can also find a crusty old discussion of "having" in  this transcript .

I hope this helps!

KASSALMD · Answer

B is correct. I don't know about all of you but I don't go by the rules of grammar at all. In fact, I don't even know more than half the technical things that you all discuss. I am sure when I was in school I read and learnt those things but they have been long forgotten. I simply go by the way I WOULD speak a particular sentence. English is a strange language in a certain sense. What may seem correct in one context may not seem correct in another. The only way to tackle these questions, I think, is to imagine yourself speaking the sentence with your eyes closed and feel if it sounds alright. Now, this may not work for everybody but it does for me.
This particular question, it is my belief, is a perfect example that there are no rules in English (if you know what I mean)!

tomirisk · Answer

To me a structure of the sentence has the following logic:

Industrialization and modern methods...have improved the standard of living...while introducing dangerous chemical pollutants...  have gone unregulated since they (pollutants) were developed...

using 2/3 rule:
While vs. but - While wins. so we can eliminate D&E
In C "which" modifies time
 A says that "Industrialization and methods of insects contorol..having gone (sounding awkward at least) unregulated." I think the meaning is distorted.

So B wins.

godot53 · Answer

I am not sure what change in meaning is referred above in these two examples, but the easiest way to eliminate C is "which have". "at the same time" is an adverb/adjective - so, "which" cannot refer back to pollutants. All, I can see that in the second option " They have introduced 100,000 pollutant at the same time ", "at the same time" is clearly ambiguous - an adverb for the action "have introduced", in line with the preceding action "have improved", or an adjective for the "1000 pollutants" . By placing "at the same time" in the beginning, as in B, we are sure that its an adverb, thus no ambiguity. Having said that, I would not rely on this difference in exam scenario. The "which" error is enough to eliminate C in so called 2 seconds !! Cheers !! :-D

GMATNinja · Answer

The short answer is that because "while" is not a simple parallelism trigger (like "and"), parallelism is not strictly required when using "while."

Check out  this post  for more on that, and let us know if you still have questions!

adalfu · Answer

not redudant at all...

while (signals contrast) at the same time (signals 'in conjunction with') ... how's that redundant?

EducationAisle · Answer

Hi  kavach , the usage of  that  is in fact most appropriate, since  that  (when used as a relative pronoun) can  only  modify  non-persons  ( pollutants  here).

p.s. Our book    EducationAisle Sentence Correction Nirvana    discusses  the usage of  that  , its application and examples in significant detail. If you or someone is interested, PM me your email-id; I can mail the corresponding section.

MadaraU · Answer

Can someone please explain how in the world phrase "introducing some 100,000 dangerous chemical pollutants" modifies "industrialization and modern methods of insect control". As for the present participle phrase isn't it important to touch the noun its modifying.

Industrialization and modern methods of insect control have improved the standard of living around the globe while at the same time  introducing some 100,000 dangerous chemical pollutants  that have gone virtually unregulated since they were developed more than 50 years ago.

Basshead · Answer

Industrialization and modern methods of insect control have improved the standard of living around the globe  while at the same time they have introduced some 100,000 dangerous chemical pollutants, having  gone virtually unregulated since they were developed more than 50 years ago.

(A) while at the same time they have introduced some 100,000 dangerous chemical pollutants, having

- 'having' modifies the  entire  preceding clause. The subject of the preceding clause is the subject for the participle. In this case 'having' modifies industrial methods. This is not the intended meaning -- the  chemical pollutants , not the industrial methods, have gone unregulated!

(B) while at the same time introducing some 100,000 dangerous chemical pollutants that have

- Correct

(C) while they have introduced some 100,000 dangerous chemical pollutants at the same time, which have

- 'at the same time' is a misplaced modifier. As a result, 'which' does not properly refer to anything in this sentence.

(D) but introducing some 100,000 dangerous chemical pollutants at the same time that have

- 'but' is a coordinating conjunction that requires parallelism. "have improved" is a  verb  and "introducing.." is a  participle . NOT parallel.

(E) but at the same time introducing some 100,000 dangerous chemical pollutants, having

- 'but' is a coordinating conjunction that requires parallelism. "have improved" is a  verb  and "introducing.." is a  participle . NOT parallel.
- 'having' modifies the  entire  preceding clause. The subject of the preceding clause is the subject for the participle. In this case 'having' modifies industrial methods. This is not the intended meaning -- the  chemical pollutants , not the industrial methods, have gone unregulated!

KarishmaB · Answer

First of all, here is a bit about the 'while' adverbial clause from my book: Screenshot 2023-04-20 at 4.53.18 PM.png Look at the main point of the original sentence now. A and B have improved the standard of living while at the same time introducing many pollutants that have gone unregulated since they were developed more than 50 years ago. The point is that A and B have done some good but at the same time, they have had some ill effects too. (A) while at the same time they have introduced some 100,000 dangerous chemical pollutants, having 'having gone unregulated' is perfect participle that makes us expect another action. Having gone unregulated for so long, the average concentration of pollutants in rivers has reached dangerous levels. It gives a cause for an effect. (B) while at the same time introducing some 100,000 dangerous chemical pollutants that have uses while adverbial phrase 'while introducing ...' because the subject is the same. Uses a 'that clause' to talk about the pollutants. All good. (C) while they have introduced some 100,000 dangerous chemical pollutants at the same time, which have The pollutants have not been introduced at the same time. Here it seems that the 100,000 dangerous chemicals were introduced at the same time. We want to say that the action of introducing was done at the same time as the action of improving the quality of life. (D) but introducing some 100,000 dangerous chemical pollutants at the same time that have (E) but at the same time introducing some 100,000 dangerous chemical pollutants, having 'but' needs a clause. We cannot use a participle with 'but.' Also, in (D), 'at the same time' modifies intro of the 100,000 chemicals. In (E), 'having gone unregulated' is used. These are the same errors as found above in options (C) and (A). Answer (B)

abhas59 · Answer

Its close between B & D.
I will go with B as 'that' clause in the end modifies pollutants that have gone unregulated.
'that' clause modifies time in D instead of pollutants located in the end of sentence.

kivalo · Answer

Can some explain to me the way 'introducing' is used in B. If it is a verb, how can it be parallel to 'have improved' ??? In case it is a present participle, how can it stand alongside 'while', which I understand is a subordinating conjunction that requires a full clause?
Thank you.

adkikani · Answer

GMATNinja   generis   VeritasKarishma   AjiteshArun   GMATninja2

I find too many ambiguities in this official question.
Do not -while- mean same as - at the same time, other than contrast.
have improved and introducing are at all parallel in OA.

Also having with coma before or after subject always behaves as past perfect action.
Am I correct?

E.g. Having studied for 2 hours, Samiya went to play badminton.
Earlier action: Studying.
Later action: playing

This is the same as:
Samiya went to play badminton, having studied for 2 hours,

Can you help what I am missing?

GMATNinja · Answer

Check out  this post  from earlier in the thread for a not-so-satisfying response to your question!

Industrialization and modern methods of insect control have improved

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GMAT Sentence Correction (SC - EA only) Questions

Industrialization and modern methods of insect control have improved

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