Answer: Language acquisition
Explanation:
Language acquisition is defined as the ability in which language is recognized and understood .It helps humans to use this language in the form of meaningful sentences for communication. Language awareness feature is also induced through language acquisition.
According to the question,Dr. Nabuto is studying language acquisition as he is interested in learning additional language so that he can know about the use for language done by people in future life.e is also using Lilo's class for researching.