Final answer:
The correct answer is C, age 13. Genie's case study highlights the critical period for language development and its impact on cognitive growth.
Step-by-step explanation:
The question pertains to the critical period for language development and cognitive psychology. The correct answer is Choice C, which refers to the case study of Genie, a child who did not start learning language until the age of 13 due to neglect. Her subsequent language acquisition provides insight into the effects of human bonding and language learning on cognitive development. Studies indicate that there is a critical period for language acquisition, with proficiency in learning language being highest early in life and diminishing as people age. A crucial component of early cognitive development is the ability to learn language, which is typically mastered with relative ease by children.