The Following Table Shows a Profit-Maximizing Producer's Marginal Costs

The following table shows a profit-maximizing producer's marginal costs.The firm is operating in a perfectly competitive market and has fixed costs of $500.

-Refer to the above information to answer this question.If the price is $500,what is the optimal output and what is the profit or loss?

A) 5 and a profit of $1,150.
B) 6 and a profit of $1,200.
C) 7 and a profit of $560.
D) 7 and a profit of $1,430.
E) 8 and a profit of $1,330.