Critical Reasoning

Most of AmTrans' weekly trains travel to and from Harcourt Terminal, a heavily trafficked train station. AmTrans depends for its success on running trains in all types of weather and punctual arrivals, and is consequently planning to replace half of its current trains with bullet trains, which can operate regardless of weather conditions and which can travel at twice the speed of AmTrans' current trains.

Which of the following, if true, could present the most serious disadvantage for AmTrans in replacing its current trains with bullet trains?

(A) Bullet trains would enable AmTrans to run trains in weather conditions that its current trains cannot operate in.
(B) The cost of manufacturing AmTrans' current trains so that they could travel at twice the speed they currently do is expected to decline over the next several years.
(C) The ability of the bullet trains to travel at twice the speed of current trains would enable AmTrans to eliminate the ticket refunds currently provided to passengers on trains more than 20 minutes late.
(D) None of AmTrans' competitors that use Harcourt Terminal are considering buying bullet trains.
(E) When bullet trains leave stations at high speeds, the resulting heat and friction on the tracks delays arriving trains.

OA : E