Commercial Passenger Airplanes can be equipped with a collision-avoidance radar system that provides pilots with information about the proximity of other airplanes. Because the system warns pilots to take evasive action when it indicates a possible collision, passengers are safer on airplanes with the system than on comparable airplanes not so equipped, even though the system frequently warns pilots to evade phantom airplanes.
Which one of the following is an assumption on which the argument depends?
A) Passengers feel no safer on airplanes equipped with the radar system
than on comparable airplanes not so equipped. - WRONG. A comparison is not what passage tries to make nor it depends on it.
B)
Warnings given by collision-avoidance system about phantom radar signals
are not caused by distorted radar signals. - WRONG. Even if they are given by the distorted radar signals it means that CARS is working as desired.
C) The frequency of
invalid warnings will not cause pilots routinely to disregard the system’s warnings. - CORRECT. If disregarded by pilots then CARS's effectiveness is questionable. Thus, not safer even if the system is working properly.
D) Commercial passenger airplanes are
not the only planes that can be equipped with a collision-avoidance system. - WRONG. Irrelevant. Other planes whether equipped or not is out of question.
E) The
greatest safety risk for passengers traveling on commercial passenger airplanes is that of midair collision. - WRONG. It's not about the greatest risk or safest risk but how warning signals make it safer for passengers.
Answer C.