Answer:
The answer is A
Explanation:
Sadness is the theme in the second stanza
How were the fireworks display last fourth of July
Compound word.
Don't mind the "x" and "z" if you look at the included image.
This might help. It is the image.
http://www.enchantedlearning.com/alphabet/wordforeachletter/compoundwords/answerstiny.GIF
I would say D, since A and B would be highly irrelevant. C sounds like a possible answer, but could still be viewed as irrelevant since it doesn't actually contain info about MP3 players.