Electrical engineers have repeatedly demonstrated that the best solid-state amplifiers are indistinguishable from the best vacuum-tube amplifiers with respect to the characteristics commonly measured in evaluating the quality of an amplifier’s musical reproduction. Therefore, those music lovers who insist that recorded music sounds better when played with the best vacuum tube amplifier must be imagining the difference in quality that they claim to hear.
Which one of the following, if true, most seriously weakens the argument?
(A) Many people cannot tell from listening to it whether a recording is being played with a very good solid-state amplifier or a very good vacuum-tube amplifier.
(It's one of the part of the passage given above, whobis testifying that the sounds produced by both can't be distinguished so A can't be the option)
(B) The range of variation with respect to the quality of musical reproduction is greater for vacuum tube amplifiers than for solid-state amplifiers.
( This is surely differentiating the vaccum tube amplifier with solid state amplifier, but is not weakening the passage because it's stated that the sound is almost similar which can hardly be distinguished, so crossed out)
(C) Some of the characteristics that are important in determining how music sounds to a listener cannot be measured.
( This statement is weakening the passage as the music quality is just not depended upon the amplifier, there are other factors which distinguish them) (Correct one)
(D) Solid-state amplifiers are more compact, use less power, and generate less heat than vacuum-tube amplifiers that produce a comparable volume of sound.
(Same as B, differentiating but is not mentioned in passage, so can't be stated surely, so crossed out)
(E) Some vacuum-tube amplifiers are clearly superior to some solid-state amplifiers with respect to characteristics commonly measured in the laboratory to evaluate the quality of an amplifier’s musical reproduction.
( Again you can't determine whose quality is best or worst, the only thing which is given in passage as they sound similar)
I choose C because the passage is already stating both sounds are similar so differentiating between them as done in B D And E will be of no use. Only The other aspect of music can be taken into consideration as stated in C. Hope this might be helpful.
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