What is the relationship characterized by producers increasing output as prices rise?

The relationship characterized by producers increasing output as prices rise is known as supply. This principle is rooted in the law of supply, which states that, all else being equal, an increase in the price of a good or service will lead to an increase in the quantity supplied. Producers are motivated by the potential for higher profits when prices increase, prompting them to allocate more resources to production to meet the anticipated demand. As prices rise, it typically becomes more viable for firms to cover their costs and potentially gain a larger profit margin, thereby encouraging increased output.

In contrast, demand involves the quantity of a good that consumers are willing to purchase at various price levels, monopoly refers to a market structure where a single firm dominates the market, and equilibrium represents the point where the quantity supplied equals the quantity demanded in the market. Therefore, the correct answer, reflecting the direct relationship between price and output from producers, is indeed supply.