Suppose a Price-Taking Firm Produces 400 Units at Its Optimal

Suppose a price-taking firm produces 400 units at its optimal output level.At that output rate,marginal cost is $200,average total cost is $240,and average variable cost is $170.The firm will be forced to go out of business in the short run if _____

A) the market price equals $200 per unit.
B) the market price is between $170 per unit and $240 per unit.
C) the market price falls below $170 per unit.
D) the market price is between $200 per unit and $240 per unit.
E) the market price equals $240 per unit.