What does supply refer to in economics?

Supply in economics specifically refers to the total quantity of a good or service that producers are willing and able to sell at various prices over a specific period. This concept captures the relationship between price and quantity supplied, demonstrating how the availability of goods changes in response to shifts in price levels.

When prices increase, producers are typically motivated to supply more of a good because the potential for higher revenues makes it worthwhile; conversely, if prices fall, the incentive to produce may decrease, leading to a reduction in quantity supplied. Understanding supply in this manner helps illustrate how market dynamics operate, influencing factors such as production decisions, pricing strategies, and ultimately, the overall market equilibrium.

The other options focus on different aspects: one mentions the selling price of goods, which is a separate element of market dynamics, while another option relates to demand rather than supply, and the last refers to the quality of goods produced, which is a characteristic but not a measure of supply in economic terms.