求问一道boldface的题 GWD中的

mogu724

During the past year, Pro-Tect Insurance Company's total payouts on car-theft claims were larger than the company can afford to sustain. Pro-Tect cannot reduce the number of car-theft policies it carries, so cannot protect itself against continued large payouts that way. Therefore, Pro-Tect has decided to offer a discount to holders of car-theft policies whose cars have antitheft devices. Many policyholders will respond to the discount by installing antitheft devices, since the amount of the discount will within two years typically more than cover the cost of installation. Thus, because cars with antitheft devices are rarely stolen, Pro-Tect's plan is likely to reduce its annual payouts.In the argument above, the two portions in boldface play which of the following roles?

AThe first rules out a certain strategy for achieving a goal; the second presents the strategy that was adopted instead and whose effectiveness the argument assesses.
BThe first is a judgment made in support of a certain conclusion; the second is that conclusion
.CThe first has been used as a consideration to support adopting a certain strategy for achieving a goal; the second reports a decision to adopt an alternative strategy.
DThe first provides evidence in favor of adopting a certain strategy for achieving a goal; the second reports a decision to pursue an alternative goal.
EThe first is a consideration offered against adopting a certain strategy for achieving a goal; the second is the main conclusion that the argument is seeking to establish.
我选的c
  理解是 第一个因为不能减少policy number ,so。。。。therefore采用第二个策略 这三句话一直是递进的 所以第一个减少policy number不可以就支持采取第二个策略了啊 C为什不对呢