Solution
The correct answer is option 3. The passage cites Stravinsky's description of music as "a form of speculation in terms of sound and time" to move beyond the nineteenth-century emotional view toward a more objective definition. This redefinition responds to earlier conceptions, reframes what music communicates, and opens the door for electronic music to qualify as music. However, nowhere does the passage suggest that Stravinsky's description provides criteria for sorting musical sounds from non-musical ones. It redefines the art of composition, not the acoustic properties that make a sound "musical." Because option 3 names something the quote does not do, it is the correct EXCEPT answer.
Option 1 is wrong as a choice for EXCEPT (it matches the passage's use of the quote). The passage explicitly contrasts the nineteenth-century emotional view with Stravinsky's twentieth-century objective view, so the quote directly responds to and expands upon earlier understandings of music.
Option 2 is wrong as a choice for EXCEPT (it matches the passage's use of the quote). By replacing the idea of music as "direct, open, emotional expression" with "speculation in terms of sound and time," the quote complicates our notion of what is communicated through music, shifting from subjective feeling to objective formal inquiry.
Option 4 is wrong as a choice for EXCEPT (it matches the passage's use of the quote). The passage states that accepting Stravinsky's more objective definition "will of course immediately bring the layman closer to an understanding of, and sympathetic response to, electronic music," thereby allowing electronic music to be classified as music.