What term describes the quantity of a commodity bought at a certain price at a given time and place?

The term that describes the quantity of a commodity that consumers are willing to buy at a certain price, at a specific time and location, is demand. Demand reflects consumer behavior and their purchasing intentions based on various factors including price, preferences, and income levels. It is fundamental to the study of economics because it helps to explain how much of a good or service will be purchased in the market, thereby influencing market dynamics.

In contrast, supply relates to the quantity of a commodity that producers are willing to sell at a particular price, which focuses on the production side of the market. Necessity refers to items or services that are essential for survival or well-being, while utility describes the satisfaction or benefit derived from consuming a good or service. Thus, demand is specifically concerned with consumer purchase decisions, making it the correct term in this context.