Answer:
C) stay the same; stay the same; increase
Step-by-step explanation:
A monpolistically competitive market is a market where there are many buyers and sellers. It has both the features of a monopoly and perfect competition.
If in the short run, the fixed cost of a monpolistically competitive firm falls, the firm would not be able to make any adjustment to production because in the short run, some factors of production are fixed. So, price and output remains the same while economic profit increases due to a reduction in cost.
Economic profit = Accounting profit - Opportunity cost