In his research of a toxic waste bill Tobias is conducting a systematic investigation what can be said about his investigation?

A. It's being done according to a system he read about in a book.
B. It's sloppy and full of irrelevant information.
C. It's being done in a fixed and methodical way.
D. It's inefficient.

I would appreciate any given responses.

C. It's being done in a fixed and methodical way.