As an example of such a transmutation, consider what Verdi made of the typical political elements of nineteenth-century opera. Generally in the plots of these operas, a hero or heroine -- usually portrayed only as an individual, unfettered by class -- is caught between the immoral corruption of the aristocracy and the doctrinaire rigidity o r secret greed of the leaders of the proletariat. Verdi transforms this naive and unlikely formulation with music of extraordinary energy and rhythmic vitality, music more subtle than it seems at first hearing. There are scenes and arias that still sound like calls to arms and were clearly understood as such when they were first performed. Such pieces lend an immediacy to the otherwise veiled political message of these operas and call up feelings beyond those of the opera itself
Or consider Verdi&39;s treatment of character. Before Verdi, there were rarely any characters at all in musical drama, only a series of situations which allowed the singers to express a series of emotional states. Any attempt to find coherent psychological portrayal in these operas is misplaced ingenuity. The only coherence was the singer&39;s vocal technique: when the cast changed, new arias were almost always substituted, generally adapted from other operas. Verdi’s characters, on the other hand, have genuine consistency and integrity. Even if, in many cases, the consistency is that of pasteboard melodrama, the integrity of the character is achieved through the music: once he had become established. Verdi did not rewrite his music for different singers or countenance alterations or substitutions of somebody else&39;s arias in one of his operas, as every Eighteenth century composer had done. When he revised an opera, it was only for dramatic economy and effectiveness.
By referring to Schubert and Brahms, the author suggests that

A. the works produced in the 18th century can be all considered as trash
B. the achievements of the two artists overshadow that of Verdi
C. popular music could be applied to compositions intended as high art.
D. the term of popular music is susceptible to many definitions.