What term describes exclusive control over a product or the means of producing it?

The term that describes exclusive control over a product or the means of producing it is monopoly. A monopoly occurs when a single company or entity has significant market power, allowing it to control prices and supply of a particular good or service. This situation can arise when the resources needed for production are controlled by a single provider, or when there are high barriers to entry for potential competitors.

Having a monopoly can lead to a lack of competition in the market, which can affect consumer choice and pricing. Monopolies can exist in various industries, from utilities, where one company may control the water supply in a city, to technology, where a single software provider dominates the market.

In contrast, other terms such as oligopoly and duopoly refer to market structures where there are few firms dominating the market rather than one, and a commodity refers to a basic good used in commerce that is interchangeable with other goods of the same type. Thus, monopoly is the best fit for describing exclusive control.