请教此题

HI,

The question is in the following:

The price the government pays for standard weapons purchased from military contractors is determined by a pricing method called " historical costing".Historical costing allows contractors to protect their profits by adding a percentage increase, based on the current rate of inflation , to the previous year's contractual price.

Which of the following statements , if true, is the best basis for a criticism of historical costing as an economically sound pricing method for military contracts?

(A) The government might continue to pay for past inefficient use of funds.

(B) The rate of inflation has varied considerably over the past twenty years.

(C) The contractual price will be greatly affected by the cost of materials used for the products.

(D) Many taxpayers question the amount of money the government spends on military contracts.

(E)The pricing method based on historical cositng might not encourage the development of innovative weapons.

Can you please tell me which is the right answer and why? Additionally ,if you can tell me where this question comes from I would be most grateful.

Thanks in advance for your help!

请在标题中注明题目出处和题号，以方便后来人查询，谢谢！！

HI,版主 :

I am sorry. I do not know where it comes from exactly. I bought this set of materials from Shili three years ago.It is only said in the material that no.14 in section 5.

Thanks a lot