Shane, a sales manager, remarked that typically, her employees sincerely and positively overstate their job performance and abilities. This is an example of the effect

C) holier-than-thou

Explanation:

A holier than thou appeal refers to an attitude of superiority. It was originally used as a religious expression to show that someone was more "holy" or more religious than other people.

But this approach of feeling superior also takes place in a business when a member of the organization feels that his/her job is better and more important than the jobs and performance of the rest. It implies being super optimistic about your own abilities and capabilities, enough for them to diminish others.

E.g. how many times have you heard someone else say that if it was him/her that was doing something important, everything would be great and flow smoothly, because they are the best in doing this and that, and about everything else.