Answer:
Linguistics.
Archaeology is a person who studies human history and prehistory through the excavation of sites and the analysis of artifacts and other physical remains. This is not about language so it is out.
Aesthetics is like how things look, not language, so this is out.
Linguistics is, well, the science of language study! Someone in linguistics learns about human language and other things of the sort. This is the correct answer! :)
