Concept:Mass advertising by a large firm reduces the average cost of promotion, which is a type of marketing economy.
Explanation:When a firm uses mass advertising media, its total advertising expenditure is spread over a very large output.
This lowers the advertising cost per unit of output.
Such cost advantages related to selling, promotion, and distribution are called marketing economies of scale.
Large firms can also afford bulk purchases of raw materials, large-scale production, and wide distribution networks.
These activities reduce the unit cost of marketing and selling the product.
In contrast, managerial economies arise from specialised management, financial economies from cheaper borrowing, and welfare economies from improved worker facilities.
Mass advertising specifically benefits the marketing function of the firm.
Answer:C. marketing economies