Which of the industries above would it be most profitable to$$ monopolize?

A$.$

Outboard$$ motors, because the size of the market is relatively higher than that of other options.

B$.$Coal comma because it has an enormous dollar volume of sales comma although profits per unit are rather small.

C$.$

Chocolate$$ bars, because the profit per unit is relatively high and sales volume is high.

D$.$

Local$$ newspaper, because it has no close substitute and its regional sales are rather high.