Final answer:
A cartel is an arrangement where competitors in a market engage in explicit collusion to control prices and output quotas, acting similarly to a monopoly.
Step-by-step explanation:
When competitors in a market agree explicitly on setting common prices and output quotas, this arrangement is known as a cartel. This behavior is a form of collusion, typically occurring in an oligopoly scenario where a few firms dominate the market. By colluding, these firms attempt to act similarly to a monopoly, restricting output and setting higher prices, thereby maximizing their profits as a single entity, rather than competing with each other. However, such explicit collusion is illegal in many jurisdictions because it undermines competition and is harmful to consumers.