The correct option is D.
Marginal cost refers to the amount of money it cost a company to produce one more of a particular product while the marginal benefit refers to the benefit that is obtained as a result of producing that one extra product. Profit is maximized when the marginal cost equals the marginal benefits.
To me that is a personal question, so just describe where you live, popular places near where you live and maybe even what the people are like(nice, mean etc.)
The answer is B) due to the fact that it's a good topic to start off a paragraph with
Hope this helped :)
