[求助]请教一道题

joezhouyun

Approximately two hundred brands of personal computers are being manufactured, but we currently limit our inventory to only the eight most popular brands. We plan to increase greatly the number of computers we sell by expanding our inventory to include the ten best-selling brands.
Which of the following  points out a major weakness of the plan above?

为什么选B, C为什么不对？

B. The seven most popular brands of personal computers account for almost all computers sold.

C. As the users of personal computers become more sophisticated, they are more willing to buy less well -known brands of computers.

joezhouyun

再请教另一道:
Instead of blaming an airline accident on pilot error, investigators should find out why the error was made by analying ariplane design, airline management, and pilot training programs. For only then can changes be made to ensure that the same type error does not recur and cause another accident.

Which of following is presupposition of the argument above?

A. Pilot error is not a contributing factor in most ariline accidents.
D. Investigators of ariline accidents should contribute to prevention of future accidents.
E. Most pilots who make errors in flying will repeat their errors unless they are retrained.

选哪一个？

snow_mountain

请写明出处和全部答案好吗？

1. 原来只买8种，现在扩大到10种。B说明扩大是没有必要的。

2. 在这几个选择里，我比较倾向A。