challenge: What are some common ways the tune 'Shave and a Haircut' is used?
  
  A. As a ringtone, as a doorbell sound, and as a car alarm
  B. As a door knock, as a Morse code sequence, and on customized car horns
  C. As a song in a musical, as a jingle in a commercial, and as a ringtone
  D. As a phone busy signal, as a fax machine sound, and as a computer beep
  Answer: 