请教Prep11

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 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
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.

 请问这道题为什么选A不选D呢？ 感觉没怎么读懂A的意思~~~