Certified Financial Planner (CFP) Exam 2026 – 400 Free Practice Questions to Pass the Exam

The correct choice highlights the relationship between complementary products, which are those that are used together. When the price of one complementary product increases, it often results in a decrease in demand for the other product. This is because consumers typically purchase these products in tandem; for instance, if the price of printers rises, consumers may buy fewer printers and consequently purchase fewer ink cartridges.

The relationship is driven by the interdependence of consumer demand for these products. If one product becomes too expensive or less appealing to buy, the related complementary product is less likely to be purchased as well, as the two are utilized together. This highlights the interconnected nature of their market dynamics and how they influence one another's demand.

In contrast, products that are used in place of each other relate to substitutes and do not fall under the complementary category. Products that do not affect each other’s demand imply independence in market behavior, which also does not accurately describe complementarity. Lastly, saying that complementary products always sell at the same price is inaccurate; they can vary significantly in price and still maintain their complementary relationship.