This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Gynaecology & Obstetrics
OCP's are C/I in pts receiving: 
Select and explain. 
A. Rifampicin, B. Ethambutol, C. Streptomycin, D. Pyrazinamide
A: Rifampicin
Answer: A: Rifampicin 
Explanation: None