Answer:
Pragmatics.
Explanation:
Pragmatics is the branch of linguistics that contributes to the use of language and gives context to the language. It studies the intent of the speaker, metaphors, speech acts and other approaches of the language in physical and social context. It drives the meaning of language by taking into consideration the time, place, and manner of the words, used in a language.
Ella adjusting language behavior according to the personal and social context signifies to the pragmatic aspect of language.