Answer
B.
Entry is relatively easy; only a normal profit in the long run.
Work Step by Step
Due to lack of barriers to entry, there is free entry and exit in monopolistic market, like a perfect competition. Due to this free entry and exit, in the long run all firms earn normal profits because if they earn positive/negative profits, firms enter/exit the market due to no barriers, which shifts out/in the supply curve and price level adjusts so that each firm break evens.
