What is a supply curve?

A supply curve is fundamentally a graphical representation that illustrates the relationship between the price of a good or service and the quantity supplied by producers in a market. In particular, it typically slopes upward, reflecting the principle that, as prices increase, suppliers are willing to produce and offer more of the good in the market due to the higher potential for profit.

When evaluating the other choices, option A refers to the demand curve, which details how quantity demanded varies with price, not supply. Option C describes market equilibrium, which is where supply and demand intersect but does not represent the supply curve itself. Option D discusses consumer preferences, which are not directly related to the measurement of supply in a market. Therefore, option B is the most accurate description of a supply curve in economic terms.