An industry is a natural monopoly when
(i) the government assists the firm in maintaining the monopoly.
(ii) a single firm owns a key resource.
(iii) a single firm can supply a good or service to an entire market at a smaller cost than could two or more firms.

Respuesta :

Answer: ii -a single firm owns a key resource

Explanation:  A monopoly is a form of market structure where there is only one seller in a market offering a unique product.

Natural monopoly arises when the monopoly has an advantage over potential competitors. The advantage could be powerful economies of scale or possessing a unique raw material or technology.

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