posted by Arlynn on .
The modern hearing aid is, essentially, a miniature public-address system, which converts sound into electrical energy and then converts it back to sound again. A hearing aid can increase the sound level by sixty decibels or more, but it also distorts the sound to some extent. Speech sound somewhat tinny, just as it does over the telephone.
According to the passage, what is the disadvantage of the hearing aid?
a. It makes speech sound tinny over the telephone
b. It increases the sound level too much
c. It has to convert sound into electrical energy before converting it back again.
d. It distorts the sound
The only negative in that paragraph is that hearing aids don't convey the real sound.