Expert power usually stems from

a$.$

a person's ability to penalize the actions or behavior of another.

b$.$

a person's perceptions that his or her goals or objectives are similar to another's.

c$.$

a superior's credibility with his or her subordinates.

d$.$

a person's ability to influence the behavior of others by offering them something desirable.

e$.$

the belief that a certain person has the right to exert influence and that certain others have an obligation to accept it$.$