Expert power arises from the fact that

$q,$

a$)$ experts have specialized knowledge that others seek to use. In organizations, experts are people who can absorb uncertainty and are believed to be controlling an important resource.

$q,$

b$)$ the expertise, special skill, and knowledge that experts have is not abundantly available and this factor makes expertise a very important determinant of personal power.

$q,$

c$)$ until others in the organization learn and amass enough experience, the experts are a group of people who have no substitutes. The fewer viable substitutes for a resource, the more power control over that resource provides.

D$)$ all of the above

E$)$ None of the above