In which of the following sentences from the article “Toss these negative statements” does the author uses a more formal academic tone to emphasize a point?

A - The positive self-talk business rakes in gazillions of dollars preying on the weak and simple-minded.
B - Let’s face it; the material you’re learning may actually be tough!
C - Approaching anything with a negative attitude breeds chaos, dysfunction and a lack of success.
D - Ask the person who shovels manure on a daily basis if he or she loves the job.