急问一道PREP!

Radio station 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 Verdland 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 station with RDS technology does not decrease the station’s listening area.

(D)  In 1996 Verlanders 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.

文章中说拥有RDS技术的收音机用户没有改变，但是没有说这些拥有者以前都使用到这个技术收听到广播电台了，有一种假设就是有些用户以前有这种收音机，但是他们所在的地方收不到rds信号，没用到这个功能。如果新增的电台覆盖到了他们所在的地区，那们相应的使用rds技术收听的用户数就增加了。如果这个假设不存在，那么就说明用户数没有增加。a选项就否定了这种假设的存在。