The case of Genie and her failure to acquire meaningful language ability best supports

a. the nativist approach.

b. the limitations of bilingualism.

c. metalinguistic deficiency.

d. the critical period theory.

The case of Genie and her failure to acquire meaningful language ability best supports D. the critical period theory.

Genie was a wild child - she lived in nature, surrounded by animals and didn't have any contact with humans or human language. This is why it was really difficult for her to acquire a language once she grew older - critical period is very important when learning a language because a language is acquired fastest when the child is young.