Communicative intent appears months before children develop the motor

Question

Communicative intent appears months before children develop the motor mechanisms required for speech, and scientists have conducted research into  the physical gestures that function as a child's primary form of communication for a portion of its infancy.

A) the physical gestures that function as a child's primary form of communication for a portion of its infancy 
B) the physical gestures that function for a child's primary form of communication in a portion of its infancy 
C) physical gestures which function as a child's primary forms of communication for a portion of its infancy 
D) the physical gestures which function as the primary form of communication of children during a portion of its infancy
E) a child's primary form of communication, physical gestures which become their primary form of communication during a portion of their infancy

Source - Ready4Gmat

shameekv1989 · Answer

Communicative intent appears months before children develop the motor mechanisms required for speech, and scientists have conducted research into the physical gestures that function as a child's primary form of communication for a portion of its infancy.

A) the physical gestures that function as a child's primary form of communication for a portion of its infancy
B) the physical gestures that function for a child's primary form of communication in a portion of its infancy
C) physical gestures which function as a child's primary forms of communication for a portion of its infancy
D) the physical gestures which function as the primary form of communication of children during a portion of its infancy
E) a child's primary form of communication, physical gestures which become their primary form of communication during a portion of their infancy

function for vs function as :- 
function as a -> Correct idiom
Eliminate B

physical gestures vs the physical gestures :-
we are talking about specific physical gestures hence the physical gestures should be correct
Eliminate C

children (plural) and its (singular) in D and which become their primary form are SV disagreement 
Eliminate D and E

Therefore Answer - A

PTD1995 · Answer

This is the correct answer choice. It clearly and precisely communicates the intended meaning of the sentence.
 The word "for" does not express the same intention as the word "as" from answer A)
 The use of "which" makes that this information seems non-essential, which is clearly not the case! Also the removal of the word "The" makes this answer incorrect.
 Pronoun error. Children/it is incorrect
 Pronoun error. Child/their is incorrect

Abhi077 · Answer

OFFICIAL EXPLANATION

The sentence makes sense the way it is written in (A), even though it does contain a lot of information. Still, we'll see if any of our other options phrase it more clearly. 
It is not idiomatic to say that the physical gestures "function for" something, so (B) cannot be correct. 
The correct phrasing is "function as."
Both (C) and (D) use "which" when the sentence requires "that"; to use "which," we would need a comma before. 
(D) incorrectly uses "its" to refer back to the plural "children." 
(E) repeats "primary form of communication," which results in an unnecessarily awkward sentence.

The correct answer is Choice (A)

Learnings & Insights

Relative pronoun modifiers must be close to the noun it modifies  
   Pronoun should refer back to ONE antecedent and should agree in number with that antecedent   
   'Function as' is the correct idiom and not 'function for'

ExpertsGlobal5 · Answer

Dear Friends,

Here is a detailed explanation to this question-

Choice A:  Option A maintains correct idiom and pronoun use, while conveying the intended meaning of the sentence. Thus, Option A is correct.

Choice B:  Option B utilizes the phrase "function for", which is unidiomatic; the correct form of this phrase is "function as". Thus, Option B is incorrect.

Choice C:  Option C changes the meaning of the sentence by omitting the word "the"; this omission causes the sentence to imply that scientists are studying a broad range of physical gestures, rather than specific ones which function as a child's primary form of communication for a portion of its infancy. Thus, Option C is incorrect.

Choice D:  Option D suffers from a pronoun error; the noun "children" is plural, while the pronoun "it" is singular. Thus, Option D is incorrect.

Choice E:  Option E suffers from a pronoun error; the noun "child" is singular, while the pronoun "their" is plural. Thus, Option E is incorrect.

Hence, A is the best answer choice.

All the best!
Experts' Global Team

Communicative intent appears months before children develop the motor

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Communicative intent appears months before children develop the motor

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