请教OG46-275上的一句话

(This passage was written in 1984.)

It is now possible to hear a recording of Caruso’s singing that is far superior to any made during

his lifetime. A decades-old way-cylinder recording of this great operatic tenor has been digitized,

and the digitized signal has been processed by computer to remove the extraneous sound, or

“noise,” introduced by the now “ancient” wax-cylinder recording process.

Although this digital technique needs improvements, it represents a new and superior way of

recording and processing sound which overcomes many of the limitations of analog recording. In

analog recording systems, the original sound is represented as a continuous waveform created by

variations in the sound’s amplitude over time. When analog playback systems reproduce this

waveform, however, they invariably introduce distortions. First, the waveform produced during

playback differs somewhat from the original waveform. Second, the medium that stores the analog

recording creates noise during playback which gets added to the recorded sounds.

Digital recordings, by contrast, reduce the original sound to a series of discrete numbers that

represent the sound’s waveform. Because the digital playback system “reads” only numbers, any

noise and distortion that may accumulate during storage and manipulation of the digitized signal

will have little effect: as long as the numbers remain recognizable, the original waveform will be

reconstructed with little loss in quality. However, because the waveform is continuous, while its

digital representation is composed of discrete numbers, it is impossible for digital systems to avoid

some distortion. One kind of distortion, called “sampling error,” occurs if the sound is sample (i.e.,

its amplitude is measured) too infrequently, so that the amplitude changes more than one quantum

(the smallest change in amplitude measured by the digital system) between samplings. In effect,

the sound is changing too quickly for the system to record it accurately. A second form of

distortion is “quantizing error,” which arises when the amplitude being measured is not a whole

number of quanta, forcing the digital recorder to round off. Over the long term, these errors are

random, and the noise produced (a background buzzing) is similar to analog noise except that it

only occurs when recorded sounds are being reproduced

275. Which of the following can be inferred from the passage about the digital approach to the

processing of sound?

(A)  It was developed in competition with wax-cyclinder recording technology.

(B)  It has resulted in the first distortion-free playback system.

(C)  It has been extensively applied to nonmusical sounds.

(D)  It cannot yet process music originally recorded on analog equipment.
                (E)

(E)   It is not yet capalbe of reprocessing old recordings in a completely distortion-free manner.

选E我没问题，可以对于OG对于C的解释看不懂，While the statement in choice C

could be true without contradicting any furnish enough information to justify such an inference。这句话什么意思，请高人指点，谢谢