The woodland sub-species were in isolation from contact with

section after "than" is inverted. You can read it as "either their marsh cousins or the tree-dwelling sub-species were".

Neeshpal,

You are taking the question in a wrong way. You are trying to compare the isolation of woodland sub species from other species. However, this question compare the isolation of woodland from human contact with the isolation of other species from human contact.

So, it'll be like The woodland sub-species were isolated from contact with humans longer than other species were.

That's why the correct ans is D.
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The woodland sub-species were in isolation from contact with humans longer than either their marsh cousins or the tree-dwelling sub-species.

A. in isolation from contact with humans longer than
B. isolated from contact with humans longer than
Here in option B ,it changes the meaning of the sentence.It means the woodland sub-species were isolated from contact with humans longer than they were isolated from contact with their marsh cousins or the tree-dwelling sub-species.
C. in isolation from contact with humans longer than were
D. isolated from contact with humans longer than were
This option clearly states that woodland sub-species were isolated from contact with humans longer than were their marsh cousins or the tree-dwelling sub-species isolated from contact with humans.
E. in isolation and without contacts with humans longer than

Putting B in the original sentence we have

The woodland sub-species were isolated from contact with humans longer than either their marsh cousins or the tree-dwelling sub-species.

The above sentence is ambiguous as it can mean two things

1) The woodland sub-species were isolated from contact with humans longer than they were from either their marsh cousins or the tree-dwelling sub-species. - intended meaning

2) The woodland sub-species were isolated from contact with humans longer than either their marsh cousins were isolated from contact with humans or the tree-dwelling sub-species were isolated from contact with humans.

To remove this ambiguity we need the helping/linking verb "were" as is the case in D. (Helping verbs such as was, were, do , have etc are useful in removing ambiguity )

Crick

Meaning : duration of isolation from humans for woodland sub-species was longer than for their cousins or tree-dwelling sub-species.

(A) in isolation from contact with humans longer than
Mistake-1: isolate (verb) should be preferred over isolation (noun)
Mistake-2: In this choice it seems that isolation with humans was longer than with other species. change of meaning because of wrong comparison.

(B) isolated from contact with humans longer than
Mistake-1: helping verb 'were' is required. because of missing verb the mistake conveys the wrong meaning as mentioned in mistake-2 of choice A above.

(C) in isolation from contact with humans longer than were
Mistake-1 same as (A).

(D) isolated from contact with humans longer than were
isolate (verb) fine. 'were' is present too.
Lets read it : 'Ws' were isolated....with humans longer than were 'MC' or 'TD' . sounds perfect.

(E) in isolation and without contacts with humans longer than
Mistake-1: same as (A).
Mistake-2: without contacts with human --- complete change of meaning

Dear Friends,

Here is a detailed explanation to this question-



Choice A: This answer choice utilizes the phrase "in isolation from contact with humans" rather than the far more concise "isolated from contact with humans" or "isolated from human contact", making the answer choice needlessly wordy. This answer choice also suffers from an error of meaning, as it incorrectly compares the length of "the woodland sub-species'" isolation to "their marsh cousins" and "the tree-dwelling sub-species". Thus, this answer choice is incorrect.

Choice B: This answer choice repeats the meaning error found in Option A. Thus, this answer choice is incorrect.

Choice C: This answer choice correctly compares the length of the isolation that the three sub-species experience, due to the inclusion of the helping verb "were". However, as the answer choice also uses the phrase "in isolation from contact with humans", it is needlessly wordy. Thus, this answer choice is not a very good one.

Choice D: This answer choice is quite concise and maintains proper comparison. Thus, this answer choice is correct.

Choice E: This answer choice repeats the meaning error found in Options A and B. This answer choice is also needlessly wordy and redundant due to the use of the phrase "in isolation and without contacts". Thus, this answer choice is incorrect.

Hence, D is the best answer choice.

All the best!
Experts' Global Team

CONCISION, COMPARISONS



The woodland sub-species were in isolation from contact with humans longer than either their marsh cousins or the tree-dwelling sub-species.



(A) in isolation from contact with humans longer than ----- "in isolation" is wordy. We'd prefer an adjective (isolated) rather than a prepositional phrase. Additionally, comparison is set incorrectly since it is ambiguous: WE wouldn't know whether they are comparing the "marsh cousins and tree-dwelling subspecies" to the "woodland the subspecies" or "humans".


(B) isolated from contact with humans longer than ------ Comparison is set incorrectly since it is ambiguous: WE wouldn't know whether they are comparing the "marsh cousins and tree-dwelling subspecies" to the "woodland the subspecies" or "humans".


(C) in isolation from contact with humans longer than were ------ "in isolation" is wordy. We'd prefer an adjective (isolated) rather than a prepositional phrase.


(D) isolated from contact with humans longer than were ----- CORRECT


(E) in isolation and without contacts with humans longer than ----- Extremely wordy. It should be "isolated from". "And" does not make any sense.




I hope you all find this explanation clear!!!! Cheers!!!

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