A car manufacturer, in an upgraded model of a car, introduced a new gearbox technology which improved the fuel efficiency. However, when the new model was sold with the old model, it was found that customers preferred the old model. The manufacturer concluded that fuel efficiency was not a major concern for the customers.
Which one of the following, if true, would most seriously weaken the manufacturer's conclusion?
(A) In the cities where the old model was retired, the sale of the new model flourished.
(B) Since the old model has been around for years, it was easier for customers to trust the fuel efficiency of the car in the long run
(C) 70% of the cars bought in this specific period of observation were second cars in the households, and were primarily used for long distance travel.
(D) The new model had significant design changes and the customers found the old design better.
(E) The difference in the prices of the models was insignificant.
