Answer:
The correct answer is all three options.
Explanation:
If price is reduced, the total revenue of perfectly competitive firm will not decline because a reduction in price will lead to increase in demand.
A monopoly firm is a price maker. It has a downward sloping demand curve. The demand curve is relatively elastic which means the firm needs to decrease price in order to sell more.
A firm in perfectly competitive market faces a horizontal demand curve,which means it can supply an level of output at the given price.
The demand curve in perfect competition reflects average revenue, marginal revenue and price. So, the price is equal to average and marginal revenue.
In a monopoly, the demand curve represents price and is higher than marginal revenue curve.
