大全-D-7

7.     The postal service is badly mismanaged. Forty years ago, first-class letter delivery cost only three cents. Since then, the price has increased nearly tenfold, with an actual decrease in the speed and reliability of service.

Each of the following statements, if true, would tend to weaken the argument above EXCEPT:

(A) The volume of mail handled by the postal service has increased dramatically over the last forty years.

(B) Unprecedented increases in the cost of fuel for trucks and planes have put severe upward pressures on postal delivery costs.

(C) Private delivery services usually charge more than does the postal service for comparable delivery charges.

(D) The average delivery time for a first-class letter four decades ago was actually slightly longer than it is today.（E）

(E) The average level of consumer prices overall has increased more than 300 percent over the last forty years.

为什么是E?C为什么不对呢?谢谢!!

If C is true, "Private delivery services charge more than does the postal service for comparable delivery charges", then probably the the postal service is not "badly mismanaged" as the author suggests, since the postal service is offering comparable service at lower price.

E says "The average level of consumer prices overall has increased more than 300 percent over the last forty years", but the passage tells us that "the (postal) price has increased nearly tenfold", so the consumer price inflation can not account for all the postal price increase.  So, it could be the case that the postal price increase is caused by bad management -- E does not weaken the original argument.  Therefore E is the best answer.