In Delaware County, Pennsylvania, All Homes, Businesses, and Other Organizations

In Delaware County, Pennsylvania, all homes, businesses, and other organizations purchase their water from one seller, Philadelphia Suburban Water Co. (PSWCo) . Economists refer to public utility companies like PSWCo as natural monopolies because their

A) marginal cost curves lie everywhere beneath their average fixed cost curves.
B) marginal cost curves lie everywhere beneath their demand curves.
C) average total cost curves lie everywhere above their demand curves.
D) None of the above answers is correct.