GMAT CR
Since the invention of digital readout,machine designers have rushed to replace conventional dials and gauges with digital units.Yet the digital gauge has drawbacks in somesituations.Since it presents an exact numeric value,it must be decoded andanalyzed by a human operator; its meaning cannot be read in an instantaneousscanning.An analog dial or gauge can be marked with red to alert the operatorwhen a value is entering a danger zone; a digital gauge cannot.And it isdifficult to tell whether a digital readout is increasing or decreasing overtime,while the up or down movement of a pointer on an analog gauge can bequickly and easily observed.
The author of the passage above would probably recommend the use of digital gauge in cases when
I.warning of a sudden riseor fall in value is needed
II.anoperator must read and interpret several gauges within a few seconds
III.aprecise numeric value is essential
(A) I only
(B) III only
(C) I and IIIonly
(D) II and IIIonly（B）
(E) I,II,andIII
我選的是A,這個(gè)文中完全沒(méi)有提到啊.