Q.Give economic term:
Very realistic competition in nature.

Cost incurred to promote sales = Selling cost.

Selling cost is the expenditure incurred by a firm to promote the sale of its product and to shift the demand curve in its favour. It includes spending on advertisement, free samples, gifts, window displays and salaries of salesmen.

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Odd word = Patents.

Selling cost is spending done to promote the sale of a product. The following are examples of selling cost:

• Free gifts given with a product to attract buyers.
• Advertisement hoardings displayed to publicise the brand.
• Window displays arranged to draw customers' attention. …

The odd word is Selling cost.

Total Cost (TC), Average Cost (AC) and Marginal Cost (MC) are all production cost concepts — TC is the whole cost of producing a given output, AC is cost per unit (TC divided by output), and MC is the addition to total cost from producing one more unit. Selling cost, on the other hand, is expenditure incurred to promote sales (advertisement, sales promotion, salesmen) — a feature especially of monopolistic competition …

The term described is Monopolistic Competition — the market form considered the most realistic because it reflects real-world markets of many sellers offering differentiated products.

Monopolistic competition, explained by Edward Chamberlin, is a market structure with a large number of sellers who sell differentiated (close but not identical) products — for example soaps, toothpastes, cosmetics or restaurants. Each seller has some control over the price of their own brand (an element of monopoly), yet faces stiff rivalry from close substitutes (an element of competiti …

The correct option is Selling cost — expenditure incurred by a firm to promote the sale of its product, such as advertising and salesmanship.

Production costs (total cost, average cost, marginal cost) are all incurred to produce output. Selling cost is different: it is incurred to sell output — on advertisement, publicity, sales agents, free samples and sales promotion. It is a key feature of monopolistic competition, where firms sel …