Barakah Is the Head of a Group at an Ad

Barakah is the head of a group at an ad agency working with copywriters, artists, and designers to come up with effective branding of new products. Why is it particularly important for her to keep her team happy?

A) People are more conscientious when they are in a good mood.
B) People are more cooperative when they are in a good mood.
C) People are more creative when they are in a good mood.
D) People are more efficient when they are in a good mood.
E) People are more productive when they are in a good mood.