Answer:
Informal Authority
Step-by-step explanation:
Informal Authority is a concept first elaborated by Henri Fayol. This is the type of authority that does not stem from official positions or promotions, but from other factors such as expertise, technical knowledge, and even charisma.
This is why this type of authority is known as "informal", because it may be held by a person who does not necessarily have a high position in the organization (as long as the person has some, or all the characteristics previously mentioned).