i think what this question is getting at is that there is an age or time period in music history called the Classical age which produced a multitude of common orchestral, brass, and piano movements. Some of the composers include the classics like Beethoven, Mozart, Hayden and Bach. The classical music i think that they are refering to with the lower case "c" is describing the genre of music that is either wind/brass, orchestral, piano or other instruments that did not originate in the modern times.