Answer:
The correct answer is option b.
Step-by-step explanation:
A monopolist is the only firm in its market. It is the price maker and faces a downward-sloping demand curve. There is a restriction on the entry of new firms. So the monopolist can earn more than normal profit in both short-run as well as long run. The other firms can not join the market because of barriers to entry. So unlike a perfectly competitive firm, the monopolist will continue to earn super normal profits in the long run as well.