An advantage of dextromethorphan ove codeine as an antitussive is that it.. Produces very little depression of the CNS

An advantage of dextromethorphan ove codeine as an antitussive is that it:
A. Is twice as affective
B. Is more stable
C. Has no side effects
D. Produces very little depression of the CNS
E. Has better analgesic properties.