Final answer:
Halothane is not a racemic agent because it does not have two enantiomers.
Step-by-step explanation:
Racemic agents are drugs that exist as a mixture of two enantiomers, which are mirror images of each other. The prefix 'levo-' indicates the 'l' or left-handed enantiomer, while the absence of a prefix indicates a racemic mixture. In this case, the racemic agent is halothane. Halothane is often used as a general anesthetic, but it is not a racemic agent because it does not have two enantiomers.