一个逻辑题。。。。求助

gracezz

Biometric access-control systems—those using fingerprints, voiceprints, etc., to regulate admittance to restricted areas—work by degrees of similarity, not by identity. After all, even the same finger will rarely leave exactly identical prints. Such systems can be adjusted to minimize refusals of access to legitimate access-seekers. Such adjustments, however, increase the likelihood of admitting impostors.

Which of the following conclusions is most strongly supported by the information above?

(A) If a biometric access-control system were made to work by identity, it would not produce any correct admittance decisions.

(B) If a biometric access-control system reliably prevents impostors from being admitted, it will sometimes turn away legitimate access-seekers.

(C) Biometric access-control systems are appropriate only in situations in which admittance of impostors is less of a problem than is mistaken refusal of access.

(D) Nonbiometric access-control systems—based, for example, on numerical codes—are less likely than biometric ones to admit impostors.（B）

(E) Anyone choosing an access-control system should base the choice solely on the ratio of false refusals to false admittances.

请大家看看这个题怎么出来的？

gracezz

嗯，讲得有道理！

月落乌啼

我觉得题目主要就是在说Biometric access-control systems-----不是by identity的------因此合法通过者哪怕每次的指纹有微小差别也可以通过-----即宽松了-------那么非法进入也就有了可乘之机

因此如果反过来，非法的绝对进不来了，即很严格，必须是identical，那么合法的有时也会进不来了。即B选项。

而其他所有Nonbiometric access-control systems的， work by identity的，如何选择access-control system 的，都比较无关了。

只有C选项，其实有点道理，就是既然Biometric access-control systems可以更好解决mistaken refusal of access，而自己又可能会带来admittance of impostors ，那么它就比较适合用于mistaken refusal of access问题比admittance of impostors问题更重要的情况下。但这个逻辑就没有B选项直接与原文逻辑相关，况且are appropriate “only” in situations也过于绝对。 所以要说most strongly supported ，还是B比较好