Though both are rodents, squirrels and chipmunks differ anatomically

Confused on B: does it parallel? not only “anatomically” but also “in coloration and nesting habits”

Hello Mavisdu1017,

We hope this finds you well.

To answer your query, “anatomically” and “in coloration and nesting habits” are absolutely parallel, as both are adverbial modifiers that act upon the noun "differ".

You may have been confused by the inclusion of the preposition "in"; if so, please keep in mind that prepositional phrases can also serve as adverbs.

We hope this helps.
All the best!
Experts' Global Team

Thanks for your explanation expert. But where is A wrong?

Hello ArunGour and Mavisdu1017,

We hope this finds you well.

To answer your queries, Option A is clearly inferior to Option B due to its needlessly indirect construction; Option A utilizes an independent clause "the coloration and nesting habits of each are also different" - to convey what Option B does in one modifier - "also in coloration and nesting habits".

We hope this helps.
All the best!
Experts' Global Team

Official Explanation

Read the Original Sentence Carefully, Looking for Errors:

The phrase "the coloration and nesting habits of each are also different" is confusing. The intent is to express that squirrels and chipmunks have different coloration and different nesting habits from each other. However, the clause ends with "different," leaving us to wonder: different from what?

Scan and Group the Answer Choices:

(A), (B), and (C) all begin with "squirrels and chipmunks." This is correct, since the underlined section is immediately preceded by the modifying clause, "Though both are rodents." This clause must be followed immediately by the things it modifies. (E) breaks this rule. (D) begins with "not only do squirrels and chipmunks" and so must complete this thought with "but also [they do something else]."

Eliminate Wrong Answer Choices:

There's an error in the original, so eliminate (A).

(E) is incorrect because the modifier "Though both are rodents" is not immediately followed by its objects.

(D) is incorrect because the second part of the "not only . . . but also" construction lacks a verb and so is not parallel with the first part.

(B) also uses the "not only . . . but also" structure, which requires parallel construction. In (B), the adverbial phrase "in coloration and nesting habits" is parallel to the adverb "anatomically." Both adverbs tell how the two animals differ. Also, the comparison is clearly between squirrels and chipmunks. Keep this one and consider (C).

(C) puts the squirrels and chipmunks just after the introductory modifier, but it seeks to form a compound modifier with "and also." First, the use of both words is redundant; only "and" is needed. Second, the phrase "their coloration and nesting habits" is not parallel with the adverb "anatomically." To make this an adverbial phrase, the author would have needed to, for instance, precede it with "in": squirrels and chipmunks differ anatomically and in their coloration and nesting habits .

(B) uses parallel structure with "but also" and makes clear that the differences are between squirrels and chipmunks; therefore, it's the correct answer.

TAKEAWAY: When an unclear structure gives a sentence an ambiguous meaning, pick the answer choice that clarifies the meaning and doesn't introduce any new errors.