Babies who can hear and have hearing parents who expose them to speech begin to babble at a certain age as a precursor to speaking. In the same way, deaf babies with deaf parents who communicate with them and with each other by signing begin to babble in signs at the same age. That is, they make repetitive hand gestures that constitute, within the language system of signs, the analogue of repeated syllables in speech.

The information above, if accurate, can best be used as evidence against which one of the following hypotheses?
(A) Names of persons or things are the simplest words in a language, since babies use them before using the names of actions or processes.
(B) The development of language competency in babies depends primarily on the physical maturation of the vocal tract, a process that requires speech-oriented vocal activity.
(C) In the absence of adults who communicate with each other in their presence, babies develop idiosyncratic languages.
(D) In babbling, babies are unaware that the sound or gesture combinations they use can be employed in a purposive way.
(E) The making of hand gestures by hearing babies who have hearing parents

OA is
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IMO B.

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Babies who can hear and have hearing parents who expose them to speech begin to babble at a certain age as a precursor to speaking. In the same way, deaf babies with deaf parents who communicate with them and with each other by signing begin to babble in signs at the same age. That is, they make repetitive hand gestures that constitute, within the language system of signs, the analogue of repeated syllables in speech.

Rephrase
Both at same age
For babies who can hear --> parents hearing --> stats to babble
For babies who are deaf --> parents deaf --> communicate thro signs (hand gestures)

Assump: babies communication depends on parents ability to speak

IMO :

(A) Names of persons or things are the simplest words in a language, since babies use them before using the names of actions or processes.
-- Incorrect : this doesnt relate to conclusion

(B) The development of language competency in babies depends primarily on the physical maturation of the vocal tract, a process that requires speech-oriented vocal activity.

-- Correct : This contradicts with assumption. This states that babies communication depends on physical maturation not on parents ability

(C) In the absence of adults who communicate with each other in their presence, babies develop idiosyncratic languages.
-- Incorrect : IMO seems to strengthen with argument.
(D) In babbling, babies are unaware that the sound or gesture combinations they use can be employed in a purposive way.
-- Incorrect : Irrelevant.
(E) The making of hand gestures by hearing babies who have hearing parents
-- Incorrect : IMO Irrelevant

Can any one comment on option E.
Coz according to me this seems to be contradicting with argument.
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