Which of the following statements is correct regarding the metabolism of codeine?
a) O-methylation of codeine effectively creates a safe metabolite with minimal side effects.
b) The metabolism of codeine by CYP2D6 creates a harmless metabolite with minimal side effects.
c) The metabolism of codeine by UGT2B7 creates a metabolite capable of producing euphoria.
d) The metabolism of codeine by CYP3A4 creates a harmless metabolite with minimal side effects.