According to some experts, carbon dioxide is accumulating in

As others have stated, B-D are incorrect because we need to follow the idiom "so rapidly . . . that."

E uses "if" incorrectly. Any of the following would work:

"If the present rate continues, the global concentration will double."
"If the present rate continued, the global concentration would double."
"If the present rate were to continue, the global concentration would double."

Note that in the second and third examples, we are using a form of the past tense, followed by "would." Similarly, if we are going to say "If the rate did continue," we need to use "would" rather than "will."

The first example matches with A (the correct answer). "Should the present rate continue" is another way of saying "If the present rate continues." Many people aren't going to like this choice because this is a particular idiomatic use of the word "should" that's a little fancier than what we tend to use in everyday speech. This is exactly the kind of construction that the GMAT loves to use to throw us off the trail. If you are highly comfortable with written and spoken English, you are probably accustomed to this usage, but if not, you are left wondering what "should" is doing in there.

One last problem with E is that we don't really need to say "did continue." That usage is only needed if we are contradicting another idea:

"Country X has promised to stop polluting the ocean; however, if it did continue polluting, other countries would take actions against it."

I hope this helps!
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Is it A?
According to some experts, carbon dioxide is accumulating in the atmosphere so rapidly that should the present rate of buildup continue, the global concentration of this poison will double by the end of the next century
should the present rate of buildup continue = if the present rate of buildup continue
Kudo me if it's right :D

I will go with B ..using "that" seems redundant

No, It's the phrase "so adjective or adverb that S-V (clause)".

'A' for me. idiom.. so rapidly... that.. 'E' 's usage of if is weird.

i THINK IT IS a,,,...... BECAUSE WE NEED "THAT' WITH "SO"

i pick (A).

correct idiom is "so X that Y"

that leaves (A) and (E)

(E) is weird because of "if" and "did".

According to some experts, carbon dioxide is accumulating in the atmosphere so rapidly, largely because of the burning of fossil fuels, that should the present rate of buildup continue, the global concentration of this poison will double by the end of the next century.

(A) that should the present rate of buildup continue, the global concentration of this poison
(B) should the present rate of buildup continue, the global concentration of this poison
(C) should the present rate of buildup be continued, the global concentration of this poison
(D) the global concentration of this poison, were the present rate of buildup continue,
(E) that the global concentration of this poison, if the present rate of buildup did continue,

I too will go with A. E also uses 'This'

Could anyone of you explain this please? I'm stuck up between A and E.

+1 A

Dmitry, however, MGMAT SC says that "SHOULD" should be avoided in conditional sentences. Should we be flexible in that aspect?

I chose E, however I realise I didn't read the second part of Original sentence very carefully.

I was looking for a subject after 'that' and ignored A, not realising that it also has a subject (the global concentration) after 'that' even though in a different for sentence framing.

Hi Sunny86,

Let's consider E.
[strike]According to some experts,[/strike]carbon dioxide is accumulating [strike]in the atmosphere[/strike] so rapidly, [strike]largely because of the burning of fossil fuels[/strike], that the global concentration [strike]of this poison[/strike], if the present rate of buildup did continue, will double by the end of the next century.

After removing all middleman, final version will look like below sentence:
carbon dioxide is accumulating so rapidly,that the global concentration of X, if the present rate of buildup did continue,will double by the end of the next century.

Now see if "if the present rate of buildup did continue" serves any purpose in sentence. It can not modify either "poison" or "concentration" but still there unnecessarily between subject ( Global concentration) and verb (will double).

It might be correct when it comes at the end.
carbon dioxide is accumulating so rapidly,that the global concentration of X will double by the end of the next century, if the present rate of buildup did continue.

I hope my explanation helped, if indeed please give me kudos.

E is wrong because If <Clause>, <Clause> condition is not fulfilled. There is no subject in the 'then' part for the verb 'will double'.

Can you please also explain what is wrong in option C

Shubham017 B-D is meant to include C (read it as "B through D"). Like B and D, answer choice C is missing the crucial word "that." If we say "X is happening SO MUCH" and then we want to show the result, we need to link the two parts with "that." "X is happening so much that Y is now happening."
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Hi DmitryFarber

Whats the role of "should the present rate of buildup continue". Is it a clause? I'm not able to get the subject & verb.

Thanks

Hello KittyDoodles,

We hope this finds you well.

To answer your query, "should the present rate of buildup continue" is actually a phrase, specifically a conditional phrase.

We hope this helps.
All the best!
Experts' Global Team
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Would E be a correct sentence had it used
that the global concentration of this poison, if the present rate of buildup continues,

Hi, DmitryFarber


If the sentence in option E would rathe be

that the global concentration of this poison, if the present rate of buildup were to continue,

Then out of A & E which option to select. Please clarify me.