Scientists believe that unlike the males of most species of moth, the

D.
by the use of can be simply expressed by using
and last THEY in A is redundant. A and B out.

C is out because By atrracting is not correct usage. Even though we assume it were to keep parallelizm by must be used before using olfactory.

E. logically Call and Atract must be parallel.

The use of the verb 'call' should eliminate 'attracting'.

So, B,C & E out.

A - they attract is unnecessary. Just 'attract' will do.

D - My choice.

A clear parallelism question.
1. whistling = using
2. rather than
A. "by the use" - incorrect.
B. same as A.
C. by using sounds wrong.
Only D & E have "using". D is correct because it uses the idiom rather than (the same one that appears in the end of the sentence).

idea is to make "call" and "attract" parallel. Only option D does that.

(A) by the use of acoustical signals, but not olfactory ones, and they attract

(B) by the use of acoustical signals instead of using olfactory ones, and attracting

(C) by using acoustical signals, not using olfactory ones, and by attracting

(D) using acoustical signals, rather than olfactory ones, and attract

(E) using acoustical signals, but not olfactory ones, and attracting

=====================Hit kudos if it helped pls==============

I think that "by the use"is wrong grammatically, not idiomatic
we have to use 'with' before a noun to show a method of a main verb

I write with a pen
I learn gmat with a good spirit

we do not use "by" , anyone know, pls, show it here

we can use "by doing" or "doing" to show a method of a main verb in the main clause.

we can use "by" showing a method of a noun

the extraction by the use of chemicals is good
requirement by the program is high

those sentences possibly is correct

Correct option along with the non-underlined portion-

Scientists believe that unlike the males of most species of moth, the male whistling moths of Nambung, Australia, call female moths to them using acoustical signals, rather than olfactory ones, and that attract their mates during the day, rather than at night.

My doubt is that- Why we dont need THAT (marked in red) for parallelism?

It would be great if someone can clarify it.

Regards,
Tamal

"by+noun" is not used to show the means with which action in the main clause is done. only some idioms allow this case
I go by plain/by train.

normally we use "doing" or "by doing" to show the means with which the action in the main clause is done. I think. both doing and by+doing are the same

I learn gmat by reading a lot.

"by use of acoustic signal" in choice A and B is not idiomatic.

This question tests you on the concept of parallelism.

The first clue here is the phrase ‘call female moths.’ This means that the next verb should agree with this form – simple present.
In other words, this is how the two actions/verbs will observe parallelism.

The sentence is saying that male whistling moths call using acoustical signals and attract their mates during the day.

It’s elegant to say ‘using’ instead of saying ‘by the use of’ – this is a matter of construction.

Let’s look at the options now:

(A) by the use of acoustical signals, but not olfactory ones, and they attract - Eliminate

(B) by the use of acoustical signals instead of using olfactory ones, and attracting - Eliminate

(C) by using acoustical signals, not using olfactory ones, and by attracting - Eliminate

(D) using acoustical signals, rather than olfactory ones, and attract

(E) using acoustical signals, but not olfactory ones, and attracting - Eliminate

Based on the two errors that are pointed out in red, we can eliminate Options A, B, C, and E.

Option D is the best choice.

Hope this helps!

A and B are wordy

in between C, D and E, parallelism is only correct in D

Dear experts,

I have 2 questions.

1) How we actually know that "attract" must be parallel with "call" or "using"?

2) Is "using (present participle)" without "by" correct and not ambiguous? It may modify verb "call" (How the male moths call) or modify "them"? Generally, if present participle comes immediately after noun without comma, it will be supposed to modify the closet noun. Why (D) is acceptable?

Thank you in advance

Use the context.

Using acoustical signals is a description of how males communicate with females. The part starting with "attract" does not contain additional specifics about male communication, so it would make no sense to put that part in parallel with using acoustical signals.

Instead, these are two separate observations about the behavior of male moths: /1/ they use auditory signaling, and /2/ they attract females during daytime hours.





Modifiers NEVER apply to object pronouns (him, her, them, etc).

(It's possible to put a modifier on a subject pronoun—e.g., He who hesitates is lost—but that's more of a literary/poetic sort of thing and is extremely unlikely to show up on this test.)

Hi RonTargetTestPrep i remember you said "using" can be functioned as a preposition. Is the "using" here the same case?

Hello louisinau,

We hope this finds you well.

To answer your query, here "using" serves as an adverb that modifies the verb "call".

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

Yes! "Using", in this case, works in much the same way as "with". (with + TOOL, or with + METHOD/TECHNIQUE[/i], is a common idiom used to state the means or methodology used to accomplish something)

We could also substitute "by means of" for "using" here. (A little bit wordy, so not quite as good—but still a workable sentence.)

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