Same as always I need help asap

C

Explanation:

C is the only one that makes since i think mark as brainiest if correct sorry if im wrong.

b. changing “it’s” to “it is”

Informal writing uses contractions. To get rid of this informal writing, the author must change to a formal styles. The correct choice is "it is". This eliminates the contraction "it's". The other options only make the writing informal. The words "undertake", "investigate", and "job" are specific and create a formal tone. Switching them for "go for", "check out" and "gig" would make the writing too informal for its purpose.