prep2-11 没讨论过的疑问

pmoaprikn

11.   (24915-!-item-!-188;#058&001837)

Radio stations with radio datasystem (RDS) technology broadcast special program information that only radioswith an RDS feature can receive.  Between1994 and 1996, the number of RDS radio stations in Verdland increased from 250to 600.  However, since the number ofRDS-equipped radios in Verdland was about the same in 1996 as in 1994, thenumber of Verdlanders receiving the special program information probably didnot increase significantly.

Which of the following is anassumption on which the argument depends?

(A) Few if any of the RDS radiostations that began broadcasting in Verdland after 1994 broadcast to peoplewith RDS-equipped radios living in areas not previously reached by RDSstations.

(B) In 1996 most Verdlanders wholived within the listening area of an RDS station already had a radio equippedto receive RDS.

(C) Equipping a radio station withRDS technology does not decrease the station's listening area.

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

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

正确答案是A,小弟我第一次写选D
现在都搞清楚为什么A对D错了

但是在研究其他选项时,一直想不透C哪里错,求大牛指点!
小弟想法如下:
原题结论:虽然station数目增加,但装RDS的radio没变,因此收听到特别节目的人增加不明显
C选项取非:装了RDS的radio station会减少收听的区域
这样不就削弱他因的结论吗??
因为是收听区域变小导致听众没有明显增加,不是因为radio数目没变阿!

还是说其实这根本是无关选项呢??要怎么判断到底有关无关??
请各位高手帮忙解答!
谢谢!

sdcar2010

C is useless.  If you negate C, you get: less AREAs are accessible to RDS signal. Then the conclusion "the number of Verdlanders receiving the special program information probably did not increase significantly" is right.  So negate C supports the argument.  But we are looking for a negation that weaken the argument for a necessary conclusion.

life2011GMAT

Radio Station (RDS) ↑,
但是 RDS radio 不变 → 收听的人数也不变

正常情况我们会认为RS 多了，收听人也应该多了，但这里推理正好相反。 如果这个推理成立，就要假设RS(RDS) 并没有在其他区域增加，所以还是原来那么多人收听的到。

C 说 does not decrease the station's listening area. 那就是说增加 listening area, 如果区域增加了，那接听到的人应该也增加的。所以A 是对的。 Few, 少许，可以就当作是没有

不知道我说明白了没？

pmoaprikn

got it!!!
xie xie~~

daliancat

楼主能不能说说D 为什么错呢？解释一下A吧，我今儿第一次看，也选的D

sdcar2010

D is repeating the first sentence of the stimulus.

随风奔跑

我觉得这题是一个架桥假设
Radio Station (RDS) ↑,  RDS radio 不变 → 收听的人数也不变
这个条件不足以推出结论，需要架个桥，也就是再提供一个假设条件。
本来RDS增多，收听人数也增多，但是结论是收听人数减少，所以需要一个量抵消收听人数变化，或者是把RDS与收听人数的关系切断。
A说很少有stations broadcast to people with RDS-equipped radios ,造成收听人数的不变