What distinguishes the supply and demand model from the short-run cost curves model?
a. Supply and demand show the interaction between consumers and producers; short-run cost curves show how product supply curves are determined.
b. Supply and demand show the flow of outputs between economic actors; short-run cost curves show the flow of inputs between suppliers.
c. Supply and demand show a product market in the long run; short-run cost curves show the product market for a set time.
d. Supply and demand show the relationship between inputs and outputs; short-run cost curves show the relationships among various inputs.