Which model shows households supplying factors of production and firms supplying goods & services?

The crowding-out effect describes a scenario where increased government spending leads to a reduction in private sector investment, primarily due to higher interest rates. This concept does not address the relationships between households and firms in terms of production and consumption, making it irrelevant to the question.

Comparative-advantage theory focuses on how individuals or nations can benefit from specializing in the production of goods in which they have a lower opportunity cost, and then trading. While it relates to production and trade, it does not specifically illustrate the flow of resources between households and firms, as required by the question.

The production-possibilities curve (PPC) demonstrates the maximum possible output combinations of two goods that an economy can produce given its resources and technology. Although it is a useful tool for analyzing trade-offs and opportunity costs, it does not depict the interactions between households and firms in supplying factors of production and goods.