John Participates in a Drinking Game at a Friend's Weekend

 John participates in a drinking game at a friend's weekend party and after a while finds himself vomiting uncontrollably. Which of the following statements is the best description of John's situation?

A) There is nothing to worry about. Everybody vomits when they drink alcohol at parties.
B) John's blood-brain barrier must be malfunctioning, as this normally would prevent the initiation of vomiting.
C) John has ingested a dangerous amount of alcohol, and his area postrema has initiated vomiting in order to remove remaining alcohol from his stomach.
D) John must have ingested other drugs in addition to alcohol, because alcohol alone will not initiate vomiting.