Market Demand Curves Are Obtained by

Market demand curves are obtained by

A) summing the quantities every consumer is willing to buy at each different price.
B) observing the prices and quantities sold in a market over time and plotting those price-quantity combinations in a graph.
C) averaging the quantities every consumer is willing to buy at each different price.
D) determining the price each consumer is willing to pay for the good and summing those prices across all consumers.
E) observing the behavior of an individual consumer in a market.