A major impediment to wide acceptance of electric vehicles even on the part of people who use their cars almost exclusively for commuting is the inability to use electric vehicles for occasional extended trips. In an attempt to make purchasing electric vehicles more attractive to commuters, one electric vehicle producer is planning to offer customers three days free rental of a conventional car for every 1,000 miles that they drive their electric vehicle. Which of the following, if true, most threatens the plan’s prospects for success?
(A) Many eclectic vehicles that are used for commercial purposes are not needed for extended trips.
(B) Because a majority of commuters drive at least 100 miles a week, the cost to the producer of making good the offer would add considerably to the already high price of electric vehicles.
(C) The relatively long time it takes to recharge the battery of an electric vehicle can easily be fitted into the regular patterns of car use characteristic of commuters.
(D) Although eclectic vehicles are essentially emission-free in actual use, generating the electricity necessary for charging an electric vehicle’s battery can burden the environment.
(E) Some family vehicles are used primarily not for commuting but for making short local trips, such as to do errands.
这道题目prep的答案给的是B，但是我认为这道题要weaken的是“这个政策能让电车更有吸引力”，而不是产生经济效益，B无关。不知道大家怎么看

商品的吸引力一来自功能，二来自价格，对比一下就是性价比。electric vehicle的功能有限，不能适应长途旅行，商家推出一个PROMOTION - 以1000MILES换THREE DAYS FREE RENTAL OF CONVENTIONAL CAR以解决顾客需要解决LONG TRIP的需求，但C中所指出的是electric vehicle每周至少累积100里程，那这样就使得人们使用PROMOTION的门槛大大降低了，这项PROMOTION的成本就会转移到商品售价上，add considerably to the already high price of electric vehicles，从而降低了商品的吸引力，所以threatens the plan’s prospects for success。

确实。
add considerably to the already high price of electric vehicles是重点
谢谢