KAPLAN OFFICIAL EXPLANATION:

The pronoun in question is that and it refers to the factory owners, but the problem is that that is a pronoun to be used only for things; people must be referred to by the pronoun who. You can eliminate (A) and (B). The remaining choices differ at the end. (D) clearly grates on the ear and can be removed. A problem quite severe in (E) is rather too cute, and the choice also distorts the meaning of the sentence (it gives the impression that all of the owners are worried about pollution, which is not the meaning of the original sentence). Go with (C).
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(A) owners that felt that pollution was a severe problem
The factory owners are living beings. That is incorrect.
(B) owners which felt that pollution was a severe problem
The factory owners are living beings. which is incorrect.
(C) owners who felt that pollution was a severe problem
Correct.
(D) owners who felt that pollution to be a severe problem
That pollution to be a severe problem - is incorrect. That has to be followed by a clause.
(E) owners, feeling that pollution was a problem quite severe,
" a severe problem " is better than "a problem quite severe"

C

IMO C

(A) owners that felt that pollution was a severe problem
- incorrect use of "that" with owners. Eliminate

(B) owners which felt that pollution was a severe problem
- incorrect use of "which" with owners Eliminate

(C) owners who felt that pollution was a severe problem
- Correct. Keep

(D) owners who felt that pollution to be a severe problem
- awkward phrasing. Eliminate

(E) owners, feeling that pollution was a problem quite severe,
- Wrongly made as a modifier. Eliminate

I picked (C). It took me 43 seconds.

(A) When antecedent is people (such as "the factory owners"), "who" should be used.
(B) See above.
(D) After "that", a subordinate clause should follow. "pollution to be a severe problem" is not a clause.
(E) "a problem quite severe" is quite awkward.
This option also conveys different meanings：
In other options, the sentence indicates that some factory owners do not share the same feeling or want the reformed system.
In (E), the sentence states that all owners feel the same.
Because we cannot guess the writer's intension, the meaning change cannot be used to eliminate E.

Each of the factory owners that felt that pollution was a severe problem wanted a drastically reformed system of industrial waste disposal in the area.

(C) owners who felt that pollution was a severe problem

C gives us the correct usage of who and conveys us the actual meaning of the sentence.

(A) owners that felt that pollution was a severe problem
'Who' is used to modify people and NOT 'that'.Eliminate

(B) owners which felt that pollution was a severe problem
'Who' is used to modify people and NOT 'which'.Eliminate

(C) owners who felt that pollution was a severe problem
Correct use of who and also correctly represented in simple past form.Keep

(D) owners who felt that pollution to be a severe problem
'Felt that Pollution to be' is incorrect.Eliminate

(E) owners, feeling that pollution was a problem quite severe,
We need the information present in commas in this option because we are specially pointing to only those people who felt that pollution was a severe problem. By keeping this piece in between comma, we are making it non-essential and such usage is incorrect .Eliminate


IMO C
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Each of the factory owners that felt that pollution was a severe problem wanted a drastically reformed system of industrial waste disposal in the area.

(A) owners that felt that pollution was a severe problem -> why do we say, owners that..., it is better to use, who. Incorrect.

(B) owners which felt that pollution was a severe problem-> Same as A.

(C) owners who felt that pollution was a severe problem -> It is better. Let's keep it.

(D) owners who felt that pollution to be a severe problem -> after "that", we need a subordinate clause. It is not there. Incorrect.

(E) owners, feeling that pollution was a problem quite severe, -> Meaning changed. Incorrect.

So, I think C.

IMO C

Each of the factory owners that felt that pollution was a severe problem wanted a drastically reformed system of industrial waste disposal in the area.


(A) owners that felt that pollution was a severe problem

(B) owners which felt that pollution was a severe problem

(C) owners who felt that pollution was a severe problem

(D) owners who felt that pollution to be a severe problem

(E) owners, feeling that pollution was a problem quite severe,

Ans C

(A) owners that felt that pollution was a severe problem - INCORRECT
factory owners refers to people, so we need 'Who' in place of "That"

(B) owners which felt that pollution was a severe problem INCORRECT
Same error as in A

(C) owners who felt that pollution was a severe problem CORRECT
This option correctlyuses 'who' to refer to factory owners.

(D) owners who felt that pollution to be a severe problem - INCORRECT
Pollution to be a severe problem is incorrect

(E) owners, feeling that pollution was a problem quite severe,- INCORRECT
This statemen changes the meaning and mentions that all factory owners considered pollution a threat.
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Each of the factory owners that felt that pollution was a severe problem wanted a drastically reformed system of industrial waste disposal in the area.


(A) owners that felt that pollution was a severe problem
Modifier error. Owner is person.

(B) owners which felt that pollution was a severe problem
Modifier error. Owner is person.

(C) owners who felt that pollution was a severe problem
Modifier error from A & B is rectified

(D) owners who felt that pollution to be a severe problem
Verb is missing

(E) owners, feeling that pollution was a problem quite severe,
Modifier error

IMO C
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Each of the factory owners that felt that pollution was a severe problem wanted a drastically reformed system of industrial waste disposal in the area.


(A) owners that felt that pollution was a severe problem - that is incorrect

(B) owners which felt that pollution was a severe problem - which is incorrect

(C) owners who felt that pollution was a severe problem - Correct

(D) owners who felt that pollution to be a severe problem - to be (infinitive) incorrect

(E) owners, feeling that pollution was a problem quite severe, - Incorrect sentence formation

Each of the factory owners that felt that pollution was a severe problem wanted a drastically reformed system of industrial waste disposal in the area.


(A) owners that felt that pollution was a severe problem Incorrect

who require after owners

(B) owners which felt that pollution was a severe problem Incorrect

same as A

(C) owners who felt that pollution was a severe problem Correct

(D) owners who felt that pollution to be a severe problem Incorrect

past form form require, infinitive form wrong

(E) owners, feeling that pollution was a problem quite severe, Incorrect

modifier problem, feeling modifies each owners; misplaced quite severe

Guys, why are people obsessed with the so called original choice? Does that choice really indicate the intended meaning? E is wrong for other reasons but I've seen many explanations that say "deviates from the meaning in the original choice". I doubt the GMAT would give us 2 options that are grammatically and logically sound but one matches the meaning in option A and the other doesn't. What are your thoughts?