If the price of quinoa, a substitute for rice, increases, what effect does this have on the price and quantity of rice?

When the price of quinoa, which is a substitute for rice, increases, consumers are likely to shift their purchasing behavior due to the higher cost of quinoa. As quinoa becomes more expensive, some consumers will find quinoa less appealing and will start to purchase more rice instead.

This increase in demand for rice will lead to a rise in both the price and quantity of rice sold in the market. When demand for a product increases, producers typically respond by raising prices, and at the same time, they increase production to meet the higher demand. Therefore, the correct answer indicates that both the price and quantity of rice increase in response to the increased price of its substitute, quinoa.

The other options do not accurately reflect the dynamics of demand shifts in relation to substitutes and their effects on price and quantity in the market.