Naked mole rats form colonies of approximately 20 animals, each of which consists of a single reprroductive female and workers that defend her

A. ....
B. with each of them consisting
C. each colony consisting
D. and each of them consist
E. and each colony consisting

",and" can be used in the following situations:

1) to join two independent clauses
2) to separate the last element in a series of three or more parallel items
3) when the phrase before the "and" is set off by commas; note that in this case the ",and" is effectively there by accident, because the comma is only there as a result of the preceding clause

The ,and create a sort of clause that follows the first one but this not convey the meaning of the sentence.

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Your understand about "that" is totally wrong. THAT in this case is the relative pronoun, so THAT can modify WORKERS in order to make more clear meaning "what are workers doing?". Your understanding: "THAT is singular, worker is plural" is wrong. Moreover, WORKERS here are animals, not people => cannot use WHO.
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In E, the structure is totally changed. E is a compound sentence using two clauses and joining them with the conjunction – and -. In a compound sentence, you do need minimum two subjects and two verbs. (You can skip the subject for the second cluse, if the same subject of the first clause can stand good for the second)

E. and each colony consisting; Here the second clause after the –and - has a subject - each colony - but no verb; consisting is not a verb but a present participle; So, E is a fragment
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An absolute phrase modifier as the name implies (just a phrase, not a clause and hence will have no verb) is a group of words that describe some action or gives additional info about something it mostly follows or modifies. It is never conjugated with a conjunction such as which or and in order to conncet it to the main clause except by a comma. An absolute phrase embraces the entire preceding clause, explaining some function or nature
On the contrary an appositive is a synonym of a noun or some noun theme, and even one can replace the modified noun with the modified. In addition, the appositive modifier is just placed next to the noun it modifies, either before or after.

Let us now apply this theory.

The modifier has no verb; it is not conjugated with a conjunction but is connected with a comma. The modifier describes the nature of composition of the colonies in question. You cannot replace the any part of the previous clause, with the modifier by itself. In addition, the modifier does not follow its noun so the given phrase is an absolute modifier rather than an appositive.
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Alicia Helle, an online student at the UW, "Obtaining my degree online has been a blessing. With two small children, I am able to work when it is convenient for my family and me. I have nothing but positive comments and experiences from my time at UW-Stout.”

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Hi,
Skamal

I have attached a file that I have prepared on this topic; Pl see if that helps you

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Alicia Helle, an online student at the UW, "Obtaining my degree online has been a blessing. With two small children, I am able to work when it is convenient for my family and me. I have nothing but positive comments and experiences from my time at UW-Stout.”

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i think its an incomplete sentence or as you say a fragment since there is no verb defining/supporting "Naked Mole Rats".

(A) each of which consists --- This is a run-on sentence, as only a comma separates the two ICs. In this structure, ‘each’ is the subject of the second IC and of which is a middleman.
(B) with each of them consisting --- The problem is the reference of ‘them’
(C)each colony consisting --- correct choice
(D)and each of them consist--- 1. SV error and 2. Pronoun ambiguity
(E) and each colony consisting --- fragment
Of course, choices A, B and D can be dropped because of pronoun ambiguity, although logically one might argue that either ‘which’ or ‘them’ simply stands for only colonies. Neither each of the rats nor the animals can individually have a single reproductive female and workers within themselves, while the colonies each can very well have both the features. But when there is such a blatant gap between existing structure and intended logic, I think it is safe to keep off.
But more importantly, why is C better than E? It is because of the correct grammatical structure. C is a simple sentence, consisting of a subject, a verb primarily and then a modifier that gives some more info about the previous clause. This is a concise acceptable structure.
In E, on the other hand, the structure is totally defective. We are trying to form a compound sentences with two ICs, with the help of a coordinating conjunction ’and’. But the second IC is no IC but a phrase without a verb. So this portion is a fragment. So Ace99 is indeed correct, if he wants to call E a fragment, but A as a run-on.
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Alicia Helle, an online student at the UW, "Obtaining my degree online has been a blessing. With two small children, I am able to work when it is convenient for my family and me. I have nothing but positive comments and experiences from my time at UW-Stout.”

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All duplicate threads on this topic have been merged.

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Collection of Questions: .... Verbal Challenge 1.1: SC Questions .... Verbal Challenge 1.2: CR Questions

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