One automobile manufacturer has announced plans to increase the average fuel efficiency of its sport utility vehicles by 25 percent over the next five years, amounting to roughly five miles per gallon, and representing the first significant change in the fuel efficiency of any class of passenger vehicle in almost two decades.

(A) amounting to rougly five miles per gallon, and representing
(B) amounting to rougly five miles per gallon, and it would represent
(C) an increase that would amount to roughly five miles per gallon and it would represent
(D) an increase that would amount to roughly five miles per gallon and would represent
(E) which is an increase amounting to roughly five miles per gallon, representing

One automobile manufacturer has announced plans to increase the average fuel efficiency of its sport utility vehicles by 25 percent over the next five years, amounting to roughly five miles per gallon, and representing the first significant change in the fuel efficiency of any class of passenger vehicle in almost two decades.

(A) amounting to rougly five miles per gallon, and representing
(B) amounting to rougly five miles per gallon, and it would represent
(C) an increase that would amount to roughly five miles per gallon and it would represent
(D) an increase that would amount to roughly five miles per gallon and would represent
(E) which is an increase amounting to roughly five miles per gallon, representing

I think the answer is D. A cannot be correct because the word "to increase" needs to be represented in parallel by stating the two words "increase" and "represent" (which will be parallel). A and B both are missing the word increase or increasing. Amounting and representing are not the 2 parallel words... increase and representing are the 2 words that should be parallel. Having said that C and D are the closest and represent the correct parallelism. The only thing differentiating between the 2 is the word "it". I think "it" could mean the plan (plan to increase) or the actual increase. Hence D is the correct answer.

(D) an increase that would amount to roughly five miles per gallon and would represent

"has announced" is present perfect tense, which would require a present tense.

However, as this increase is as yet uncertain as it is in the future, "would amount to" is the ideal construct.

Again due to the uncertainty "would represent" is the ideal construct keeping all verbs in the same tense.

Deadset D.
D stands out in the first glance itself.
' an increase that would amount ' conveys the right meaning.

Late but D for ||ism
A is not parallel.
Amounting and representing is ambiguous.

Late, but (D)

We need the modal "would" to preserve the hypothetical tone of the sentence.

One automobile manufacturer has announced plans to increase the average fuel efficiency of its sport utility vehicles by 25 percent over the next five years, amounting to roughly five miles per gallon, and representing the first significant change in the fuel efficiency of any class of passenger vehicle in almost two decades.

(A) amounting to rougly five miles per gallon, and representing
before comma and ==>there is an IC..SO AFTER AND it should be IC...hence incorrect

(B) amounting to rougly five miles per gallon, and it would represent
it ==>ambiguously points towards manufacturer....and hence the meaning is changed==>manufacturer would represent the first significant change...not correct

(C) an increase that would amount to roughly five miles per gallon and it would represent ==>IT breaks the parallelism.

(D) an increase that would amount to roughly five miles per gallon and would represent ==>parallel.

(E) which is an increase amounting to roughly five miles per gallon, representing
incorrect use of which and verb-ing modifier.

hope it helps
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IMO ammounting doesnt have an error in this case

as plans will increase the fuel efficiency ....and hence resultant action is in ING form..

please correct if i am wrong.
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Nope. It is wrong but nor for the reason you mentioned. Here amounting is functioning as an adverbial clause, modifying the entire preceding clause. So the reference to noun error is unfounded

One automobile manufacturer has announced plans to increase the average fuel efficiency of its sport utility vehicles by 25 percent over the next five years, amounting to roughly five miles per gallon, and representing the first significant change in the fuel efficiency of any class of passenger vehicle in almost two decades.

(A) amounting to rougly five miles per gallon, and representing
(B) amounting to rougly five miles per gallon, and it would represent

The problem is :

amounting to roughly five miles per gallon.

It is modifying the preceding clause.

So the question is: What is amounting to five miles per gallon?

Ans. average fuel efficiency??? or increase in average fuel efficiency? You can see that a fuel efficiency of 5 miles per gallon though nonsensical can't be ignored

Whereas D says an increase that will amount to...

So we now know clearly that the increase in fuel efficiency is 5 miles/ gallon

That's why A and B are wrong.

Be very careful of , followed by ing. They are adverbial modifiers (with some rare exceptions)

there are 2 things, which makes you can not goo OA.
first, we can not realize the illogic modification.
second, we can not realize the good sentence pattern.

in choice D. a noun phrase modifies a verb/ preceding clause. but the point here is that the noun and the verb is the same

I accept you, an acceptance which everybody know

this pattern is good and logic. our choice d is similar

the company plan to increase the fuel efficiency, an increase that amount... and represent.

at first, I am uneasy with "to increase" and again "increase." but latter I see other choices are not logic. and I accept " to increase " go with "increase"