boldface题目！怎么做啊···

今天做prep的boldface题目 居然三个全错 真是彻底没信心了吧 句子之间的联系该怎么判断啊？ 以前上xdf讲的那些似乎都用不上了 还望高人指点
这里把三个题目都贴出来
1.During the past year, Pro-Tect Insurance Company's total payout on car-theft claims has been larger than the company can afford to sustain.
Pro-Tect cannot reduce the number of car-theft policies it carries, so it 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 such 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?  
(A) The first and the second are both evidence offered by the argument as support for its main conclusion.
(B) The first presents a problem a response to which the argument assesses; the second is the judgment reached by that assessment.
(C) The first is the position the argument seeks to establish; the second is a judgment the argument uses to support that position.
(D) The first is a development that the argument seeks to explain; the second is a prediction the argument makes in support of the explanation it offers.
(E) The first presents a development whose likely outcome is at issue in the argument; the second is a judgment the argument uses in support of its conclusion about that outcome.
答案是B 我选的D

2.A product that represents a clear technological advance over competing products can generally command a high price.  Because technological advances tend to be quickly surpassed and companies want to make large profits while they still can, many companies charge the greatest price the market will bear when they have such a product. But large profits on the mew product will give competitors a strong incentive to quickly match the mew product’s capabilities.  Consequently, the strategy to maximize overall profit from a new product is to charge less than the greatest possible price.

In the argument above, the two portions in boldface play which of the following roles?

A. The first is an assumption that forms the basis for a course of action that the argument criticizes; the second presents the course of action endorsed by the argument.
B. The first is a consideration raised to explain the appeal of a certain strategy; the second is a consideration raised to call into question the wisdom of adopting that strategy.
C. The first is an assumption that has been used to justify a certain strategy; the second is a consideration that is used to cast doubt on that assumption.
D. The first is a consideration raised in support of a strategy the argument endorses; the second presents grounds in support of that consideration.
E. The first is a consideration raised to show that adopting a certain strategy is unlikely to achieve the intended effect; the second is presented to explain the appeal of that strategy.
答案是C 我选的E

3.Paleontologist: About 2.8 million years ago, many species that lived near the ocean floor suffered substantial population declines.
These declines coincided with the onset of an ice age.
The notion that cold killed those bottom-dwelling creatures outright is misguided, however; temperatures near the ocean floor would have changed very little.
Nevertheless, the cold probably did cause the population declines, though indirectly.
Many bottom-dwellers depended for food on plankton, small organisms that lived close to the surface and sank to the bottom when they died.
Most probably, the plankton suffered a severe population decline as a result of sharply lower temperatures at the surface, depriving many bottom-dwellers of food.

In the paleontologist's reasoning, the two portions in boldface play which of the following roles?

(A) The first introduces the hypothesis proposed by the paleontologist; the second is a judgment offered in spelling out that hypothesis.

(B) The first introduces the hypothesis proposed by the paleontologist; the second is a position that the paleontologist opposes.

(C) The first is an explanation challenged by the paleontologist; the second is an explanation proposed by the paleontologist.

(D) The first is a judgment advanced in support of a conclusion reached by the paleontologist; the second is that conclusion.

(E) The first is a generalization put forward by the paleontologist; the second presents certain exceptional cases in which that generalization does not hold.


答案是A 我选的D


希望各位帮帮忙 这个月就要考了 不胜感激···