Which of the following is a trait of nineteenth century music?

What is "The following"? No one will know. But if I had to guess, it would be a mixture with the old and with the new. For example, Fredric Chopin Composed pieces in the nineteenth century (That's when he was in his prime) but he mixed classical music with a twist that was different from other famous predecessors (Bach, Beethoven, Mozart, etc.). So I would say a mixture of the old and new. Or something like that. Hope this helps :-)