Final answer:
A monopoly refers to a seller of a product for which there are no close substitutes. It is a market structure where a single firm dominates the market and has exclusive control over the supply of a particular product or service.
Step-by-step explanation:
A monopoly refers to a seller of a product for which there are no close substitutes. It is a market structure where a single firm dominates the market and has exclusive control over the supply of a particular product or service. An example of a monopoly is Microsoft, which has been considered a monopoly because of its domination of the operating systems market.