小安BF1究竟选哪个

cannahere

Modern navigation systems,which are found in most of today’s commercial aircraft, are made with low-powercircuitry, which is more susceptible to interference than the vacuum-tubecircuitry found in older planes. During landing, navigation systemsreceive radio signals from the airport to guide the plane to the runway.Recently, one plane with low-power circuitry veered off course during landing,its dials dimming, when a passenger turned on a laptop computer. Clearly,modern aircraft navigation systems are being put at risk by the electronicdevices that passengers carry on board, such as cassette players and laptopcomputers.
The two portions in boldface play which of the following roles?
(A) The first is a principle that the argument relies on and thesecond is a conclusion that can be drawn from the first.
(B) The first is a fact that argument relies on and the second is aconclusion that must be drawn from this argument.
(C) The first acknowledges a consideration that supports that mainposition; the second is that conclusion.
(D) The first is an evidence that supports the conclusion, thesecond is that conclusion.
(E) The first is a principle that is necessary for this argument, thesecond is a conclusion that could be drawn from this argument.

billbill

I vote E

http://forum.chasedream.com/archiver/GMAT_CR/thread-61536-4.html

cannahere

我也选B，但有看到选E的答案。。

ann110726

Vote B~