Final answer:
Advertising in monopolistic competition can increase demand and profits for firms, but creating a price war is not a reason to promote a product.
Step-by-step explanation:
In the framework of monopolistic competition, advertising can help firms increase demand for their products. A successful advertising campaign may allow a firm to sell a greater quantity or charge a higher price, or both, which can increase its profits. However, creating a price war is not a reason to promote a product, as it can lead to decreased profits for all firms involved.