Autility (such as a power company) which controls all services in a designated area is called a
a) trust.
b) cartel.
c) natural monopoly.
d) devised oligopoly.

The best and most correct answer among the choices provided by the question is the third choice "natural monopoly."

A natural monopoly is a distinct type of monopoly that may arise when there are extremely high fixed costs of distribution, such as exist when large-scale infrastructure is required to ensure supply.

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