Final answer:
The primary motivation for a company to start an online advertising campaign to highlight the superiority of their product is economic, aiming at increasing profits by boosting demand and differentiating their product in the market. Hence, option 4) is correct answer.
Step-by-step explanation:
When a company begins an online advertising campaign to promote why their product is better, their primary goal is most likely economic. By differentiating their products from competitors, companies aim to increase demand or create a more inelastic demand curve for their product, ultimately allowing them to sell greater quantities or charge a higher price. This strategy, within the framework of monopolistic competition, can significantly increase a company's profits. The motivation for such campaigns is rarely political, self-expressive, or educational in nature; rather, they are strategic efforts to enhance the company's market share and revenue.