Sentence Correction

please explain

IMO D

"Due to" means "caused by" & so is incorrectly used in A & B.

many biological traits are not the products of natural selection, favored because they enhance reproduction or survival, but are simply random by-products....

I second Vemuri...D

IMO - D.

OA please?

IMO (D)

are not X but are

I feel E.

I feel use of they in D is not clear.

While on the second thought I feel correct idiom is

not x but y

so on C would fulfill the condition because are not x but are is not the correct way.

Anyways, I am looking forward to the correct answer.

not x but y

so on C would fulfill the condition because are not x but are is not the correct way.

The correct idiom is not X but Y where X and Y are parallel in the same clause

There is no idiom tested in this example.

E.g. He is not going to work but working from home.

This is one clause

comma + coordinating conjunction introduces the new Idependent clause.

I think answer should be 'C'.

are not but are...seems to be incorrect.

A & B are wrong as correctly mentioned by Vemuri.

Guys, there is an idiom not just because of x, but because of y

In this example as per the idiom C & D are the possible answers

Paleontologist X argued that many biological traits are not because of X, favored because of Y, but are random by-products of Z

plural noun traits requires the are, and hence D must be the answer.

I was thinking of C, but subject-verb agreement, in both answers they refers to the traits, no pronoun error.

schumi_gmat wrote:

not x but y

so on C would fulfill the condition because are not x but are is not the correct way.

The correct idiom is not X but Y where X and Y are parallel in the same clause

There is no idiom tested in this example.

E.g. He is not going to work but working from home.

This is one clause

comma + coordinating conjunction introduces the new Idependent clause.

Whats an OA?

Schumi,

BUt Option D doesnot introduce a new Independent clause.

"But are" - No subject.

I picked B. because it correctly introduces the independent clause.

"because they are"

What do you think?