you feel happy when you're around someone you enjoy talking to, you feel tired after a long day of work, you feel sad when you lose your favorite pair of socks, you feel angry when your sister steals your favorite shirt, you feel scared when you think you see a shadow at the corner of your eye, you feel surprised when someone surprises you on your birthday.
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.
