The correct answer is: C. price equals total revenue.
A perfectly competitive firm is a price taker, which means that it cannot influence the market price of its product. The firm’s demand curve is therefore perfectly elastic, and its marginal revenue curve is equal to the market price.
Total revenue is the total amount of money that a firm receives from selling its products. It is calculated by multiplying the price of the product by the quantity of the product sold. For a perfectly competitive firm, total revenue is equal to the market price times the quantity sold.
Price is the amount of money that a buyer pays for a unit of a good or service. It is determined by the interaction of supply and demand in the market. For a perfectly competitive firm, the price is determined by the market and is the same for all firms in the market.
Marginal revenue is the additional revenue that a firm earns from selling one additional unit of its product. It is calculated by taking the change in total revenue and dividing it by the change in quantity sold. For a perfectly competitive firm, marginal revenue is equal to the price.
Therefore, for a perfectly competitive firm, price equals total revenue.