What economic structure is characterized by suppliers maintaining high prices and restricting competition?

The correct choice is characterized by specific practices undertaken by a group of suppliers who collude to control the market. In a cartel, companies work together to set higher prices and limit the output of goods or services in order to maximize profits. This arrangement reduces competition among the cartel members, allowing them to maintain elevated prices above what would be expected in a competitive market. Cartels orchestrate these strategies collectively, which distinguishes them from other economic structures where competition is more prevalent.

In contrast to a cartel, a monopoly exists when a single supplier dominates the entire market without any competition, whereas an oligopoly comprises a few suppliers that might be able to influence prices but do not necessarily collude as a cartel would. A free market, on the other hand, allows competition to dictate prices, functioning under the principle of supply and demand without restrictions imposed by suppliers. Thus, the defining characteristic of a cartel is the active collaboration of suppliers to manipulate market conditions, leading to high prices and limited competition.