两道OG上的CR_og-131,og-133

efficiency

OG131.
Bank depositors in the United States are all financially protected against bank failure because the government insures all individuals' bank deposits. An economist argues that this insurance is partly responsible for the high rate of bank failures, since it removes from depositors any financial incentive to find out whether the bank that holds their money is secure against failure.If depositors were more selective, then banks would need to be secure in order to compete for depositors' money.
131. Which of the following, if true, most seriously weakens the economist's argument?
(A) Before the government started to insure depositors against bank failure, there was a lower rate of bank failure than there is now.
(B) When the government did not insure deposits, frequent bank failures occurred as a result of depositors' fears of losing money in bank failures.
(C) Surveys show that a significant proportion of depositors are aware that their deposits are insured by the government.
(D) There is an upper limit on the amount of an individual's deposit that the government will insure, but very few individuals' deposits exceed thislimit.
(E) The security of a bank against failure depends on the percentage of its assets that are loaned out and also on how much risk its loans involve.
OG的解释是：The argument that deposit insurance,because of its impact on depositor's choice of banks, is partially responible for the high rate of bank failures would be weakened if deposit insurance also prevented certain bank failures.Choice B sugguests that deposit insurance does prevent certain bank failures and is thus the best answer.
我怎么看不出来B选项中deposit insurance能阻止certain bank failures.请mindfree等各位牛牛们指点一下迷津。呵呵！

还有OG133.
133. In 1960, 10 percent of every dollar paid in automobile insurance premiums went to pay costs arising from injuries incurred in car accidents. In 1990, 50 percent of every dollar paid in automobile insurance premiums went toward such costs, despite the fact that cars were much safer in 1990 than in 1960.
Which of the following, if true, best explains the discrepancy outlined above?
(A) There were fewer accidents in 1990 than in 1960.
(B) On average, people drove more slowly in 1990 than in 1960.
(C) Cars grew increasingly more expensive to repair over the period in question.
(D) The price of insurance increased more rapidly than the rate of inflation between 1960 and 1990.
(E) Health-care costs rose sharply between 1960 and 1990.
我觉得C选项也可以。按照一般的常识，如果车祸后，车也得修，必须由保险公司花钱去修呀。或者是我理解错误，injuries 只指人的费用，而不包括车？
多谢

dhhgh11

1. 完全个人意见.

我不认为B是最佳答案, 但是这里没有其它可选. 原文说high rate of bank failure是insurance造成的. 问weaken. 而B说没有insurance就会有频繁的bank failure.

个人认为最好的答案应该从insurance造成failure这个逻辑关系入手, B并没有否定这个关系. 举个例子: 甲把钱投到股市里,崩盘大跌破产, 但是不投到股市里而把现金藏床底下,通货膨胀100000%钞票成废纸破产, 藏床底下并不能很好的削弱股市造成破产的逻辑关系.

原文就是有没有insurance都fail. 但是没有其它选项相关, 而weaken只要有一点削弱就可选, B就是唯一可选答案.

希望其他人再补充