The evidence so far collected by researchers is that chimps, who are unable to understand language, share 99% of their DNA with humans, who are able to understand language. The HAR1 is what makes chimps and humans dramatically different. Putting 2 and 2 together, HAR1 is associated with language.
A – Wrong
This would weaken the hypothesis as A suggests that chimps also have a gene which is 98% identical to HAR1. This would mean that HAR1 is not related to language.
B – Correct
A mutation in HAR1 causes language impairment. This means that HAR1 is directly associated with language and damage to HAR1 causes problems in language.
C – Wrong
C does not specify what type of communication. Hoover, even if we assume that communication is related to language and that HAR1 is found in parts of the brain which are not related to communication, then this would weaken the argument .
D – Wrong
This is irrelevant to the questioning as all genes are expressed in the brain before birth.
E – Wrong
Asian, we cannot correlate communication with language. Even if we assume that communication and language are the same thing, then D actually weakens the hypothesis. If chimps were taught symbol language, then this means that they also possess a gene associated with language. Since chimps do not have HAR1, then this would mean that HAR1 is not associated with language.