Which of the following is always a violation of the antitrust law?

Refer to Figure 6.1. The monopolist earns a profit equal to 

A. $300. B. $220. C. $330. D. $550.

In considering economic profit in a market economy, it is correct to say that

A. economic profit tends to reduce the production efficiency of the economy, leading to wasted resources. B. economic profit performs an important function in allocating resources to their most highly valued uses. C. economic profit will only occur, even in the short run, as a result of imperfect competition. D. there should never be any economic profit.