To increase overall profits, an automobile dealership raised sticker p

To increase overall profits, an automobile dealership raised sticker prices by 20 percent on all of the truck models it sells, but did not raise prices on any other type of vehicle. The owner of the automobile dealership claims that this tactic alone was sufficient to increase profits, as overall revenue has almost doubled since truck prices were increased.

Which of the following, if true, most effectively weakens the owner's claim?

A. The number of other vehicle types sold did not increase.

B. The percentage of trucks sold increased after prices were raised.

C. The overall profits from all vehicles sold since prices were raised have increased.

D. The number of customers buying cars from the automobile dealership increased when the only other car dealership moved to another part of town.

E. The cost of running the dealership has more than doubled since the price increase, and the number of trucks sold has increased