求助 PREP 08 急！后天考啊。。。

datlantis

Radio stations with radio data system(RDS) technology broadcast special program information that only radios with an RDS feature can receive. Between 1994 and 1996, the number of RDS radio stations in Verdland increased from 250 to 600. However, since the number of RDS-equipped radios in Verdland was about the same in 1996 as in 1994, the number of Verdlanders receiving the special program information probably did not increase significantly.

Which of the following is an assumption on which the argument depends?

A. Few if any of the RDS radio stations that began broadcasting in Verland after 1994 broadcast to people with RDS-equipped radios living in areas not previously reached by RDS stations.

B. In 1996 most Verdlanders who lived within the listening area of an RDS station already had a radio equipped to receive RDS.

C, Equipping a radio staion with RDS technology does not decrease the station's listening area.

D. In 1996 Verdlanders who did not own radios equipped to receive RDS could not receive any programming from the RDS radio stations that began broadcasting in Verdland after 1994.

E. The RDS radio stations in Verdland in 1996 did not all offer the same type of programming.

答案是A
可以理解的是，A 选项说作者假设了新增的radio station并没有覆盖到之前没有涉及的地域，按照我在网上查到的解释的大意是说，这样就没有增大人群基数，所以才可以得出结论


我疑惑的是， 文中第一句话就说了这个special program 是需要radios with RDS feature才能接收到的， 所以按照我的理解： 无论有没有被station发射出的信号覆盖，只要没有RDS-equipped radios还是无法收听这个special program的， 也就是说即使这些新增的station的确是覆盖了以前没有覆盖地方，没有当地RDS-equipped radios的增长，当地的人还是一样收听不到special program， 所以A有没有结论都成立，无关。


请NN指教啊！！！

sdcar2010

Well, if you had that special radio in 1994, but there was no RDS signals in your area, you still could not receive RDS programs. However, if in 1996, RDS signal were available in your area, then you become a NEW listener to RDS program.

If there were a lot of people like you, the conclusion would fall apart.

datlantis

right, thanks!

Feelalive

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