Answer:
.B)face downward sloping demand curves
Explanation:
A monpolistically competitive market is when there are many firms selling differentiated products. A monpolistically competitive firm faces a downward sloping demand curve. Monopolistic firms engage in non orice competition such as advertising.
A monopoly is when there is only one firm operating in the industry. There are high barriers to entry of firms. The demand curve is downward sloping.
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