求教，逻辑大全15-13

ying178

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

答案是B。不知道A错在哪里？谢谢。

maestri

题干翻译：计量生物进入控制系统-使用指纹，声波等管理对限制地区的进入权-利用相似性等级而不是身份进行工作。毕竟，即便相同的手指也很少留下完全相同的指纹。这种系统能够通过通过调节减少合法进入者被拒绝的比例，但是，这种调节也增加了非准入者被放入的可能性。

问题：以下哪一项结论最能够被上述信息支持？

A: 如果计量生物进入控制系统通过身份识别工作，他们就无法产生出正确的准入决定
----以上信息并未涉及到身份识别的系统会怎样，只是介绍了这种控制系统的识别原理

B:如果计量生物进入控制系统可以有效地防止非准入者的进入，那么有时也会拒绝合法进入者。
---通过题干得知：“准入者”与“非准入者”被拒绝的比例是成反比的，即准入者被拒绝的可能性越小，那么非准入者被拒绝的可能性就越大，因此选B