Which is enzyme inducer.. rifampicin

Which is enzyme inducer?
a- rifampicin
b- cimetidin
c- vit. C
d- chloramephenicol
Enzyme Inducers: Phenobarbital, carbamazepine, ethanol, rifampicin, polycyclic aromatic hydrocarbons in tobacco smokers
Enzyme Inhibitors: Cimetidine ,erythromycin