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题库 / GMATAdvanced-CR-25
Since 1978 when the copyright law was changed, books that are less than fifty years old must not be photocopied without the publisher’s permission. Thus, any book that has been photocopied since 1978 without the publisher’s permission must be at least fifty years old.
The reasoning above exhibits a flaw similar to one in which of the following?
Any member of the solar system must be either a planet or a moon, so if an asteroid is neither a planet nor a moon, it must not be a member of the solar system.
Anyone who rides a city bus must buy a bus pass, and since Demetrios has a bus pass, he must be riding on a city bus.
A driver who turns right must signal, so any driver who did not signal must not have turned right.
Anyone who legally crosses a national boundary must have a passport; thus anyone who does not have a passport cannot legally cross a national boundary.
Any wage earner residing in the state must pay state taxes, so since Blodwen pays state taxes, she must be resident in the state.
原文：从1978年开始，因为没有出版商允许，50年以下的书都不能复印 ----- 所以，1978年以后，未经允许而影印的书一定是50年以上的书，也就是说，所有复印的50年以下的书，都是出版商允许的
逻辑：50年以下的书要影印，一定要经过出版商允许；没有出版商允许影印的，一定是50年以上的书
C：要右转的司机一定会打灯；没打灯的，must不是右转
D：要出国的人一定有护照；没有护照的人，cannot出国 (没有must语气那么绝对）
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