1] so the statement says "adhere to one another" --> means they stick together

2] later the statement says that even though they are together they do "exclusive" things

3] so we are looking for something which which says that first part and the second part are contradictory to each other.

(A) beating in unison and adopting -- > it is linking the 1st and 2nd part together using "and"
(B) they beat in unison while adopting -- > doesnt make 1 and 2 opposite of each other.
(C) beat in unison, and adopt -- > same , makes 1st and 2nd part erelate to each other.
(D) beating in unison yet adopting -- > yet makes the 1st and 2nd part oppose each other
(E) even though they beat in unison and adopt -- > again , has a "and" which makes 1 and 2 relate to each other.

(D) is my choice

"peculiar" signals that the sentence should carry the original meaning and then deviate at a point.

D it is...."yet" is the word which does this and also is parallel

'Peculiar' is the key here. So you need to chose an option that brings out that aspect. D is the only choice that correctly provides that.

This is a tricky one. A cursory read may lead one to infer this as a parallelism error in which case the correct answer would be C.

The singular 'feature' suggests that only one feature is being described, namely the cells adhering to one another. The second part of the sentence elaborates on what the 'pecularity' is. The pecularity is that even though the cells beat in unison they adopt orientations exclusove of one another. D correctly brings out this contrast by using the word 'yet'.

The correct answer is D.

While I agree that D seems to be the most accurate answer, I think this sentence needs a comma after the word 'heart' to read: "A peculiar feature of the embryonic mammalian circulatory system is that in the area of the heart, the cells adhere to one another,..........

Otherwise, one could easily misconstrue the part of the sentence that reads "in the area of the heart the cells adhere to one another" to be a description of an area of the heart where cells adhere to one another, giving the sentence a whole new meaning and possibly "B" as its answer.

Any thoughts anyone?

Here's my take on this question w/out repeating too much of what other people's said.

Since the last part of the sentence said, "beating in unison and adopting specialized orientations exclusive of one another.", we should see a contrasting triggering word to differentiate between "unison" and "exclusive of one another". Answer choices A, C, and E all used "and", for which it doesn't trigger the contrasting effect. Only B and D uses the right words - while (B) and yet (D).

Looking into B and D, B creates a common splice. In (B), "they beat in unison..." creates a complete sentence with a subject and a verb. In conjunction with the non-underlined sentence, the comma in between the two creates the grammatical error; therefore, (B) is incorrect. (D) fixes all the problems of this sentence.

In response to MrEasy's question with the comma after the word 'heart', I don't believe the comma is necessary since the material after the word 'heart' is a necessary clause, which requires no comma in between the two clauses. I hope I didn't confuse anyone with what I said. Also, just to go aside from that, people get bogged down by parts that are not underlined way too much; everyone should take what's given to them (the non-underlined portion) knowing that it's correct and don't question the non-underlined portion. I just wanted to point that side point out, though I'm pretty sure most people on this forum already knew that.
_________________

Hey All,

Everybody seems to have the right answer, but just to make it clear, adding a comma would NOT improve this sentence. Answer choice C is hoping to get you with a kind of shallow parallelism. We want to differentiate between the main verb "adhere", and the two subordinate verbs. To make this all one list changes the meaning for the worse.

Hope that helps!

-t

Since people have doubts about B and C :

Notice that there is no conjunction connecting the two parts of the sentence; so the second part can't be a clause!!! It can only function as participle modifiers.

B: Usage of they converts it to a clause. So this is out
C: beat is a verb, not a modifier. Only verbs in participle form can act as modifiers

For these reasons, B and C are out

The only confusing options are A and D.

Here the sentence is trying to bring out the contrasts... so we need yet. Hence A is out. D is the answer

Here's an excellent explanation given on Manhattan Prep website by Ron Purewal:

https://www.manhattanprep.com/gmat/foru ... t3201.html

Just look at the original text especially the non-underlined part. It says ' and adopting'. Therefore we need another structurally parallel modifier before the 'and'. One can safely remove B, C, and E for using a verb' beat'.
It is now easy to converge on D. we want a contrast and that is shown by the word yet. A is gone.
_________________

The sentence in its original form tries to say that cells adhere to one another. The question asked is how? The answer is beating in unison but there is a little contrast because they adopt something that is exclusive (not included). So indicate the contrast in the sentence D fits best!


Hit kudos if it helps

Posted from my mobile device

Can any one please explain the structure of this Question?
Thank you

Praveenksinha Highlighting subject in Pink, Verb in Blue, and Modifiers in Green

Option d

A peculiar feature of the embryonic mammalian circulatory system is

that in the area of the heart the cells adhere to one another, beating in unison yet adopting specialized orientations exclusive of one another.

Here the modifier in green is describing how the cells behave.
Why 'and' conjunction does not work? Here we need to express the feature that occurs simultaneously in the heart cells. Hence options such as A and C are eliminated.

To know more about how Verb-ing modifiers work and contribute to the overall structure and meaning of the sentence, please read the blog post in the link below:
https://e-gmat.com/blogs/verb-ed-modifiers-vs-verb-ing-modifiers/#:~:text=When%20verb%2Ding%20modifier%20is%20not%20separated%20from%20the%20clause,the%20context%20of%20the%20sentence.