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: Pharmacology
The most effective antitubercular drug against slow multiplying intracellular mycobacteria ? 
Select and explain. 
A. Rifampicin, B. Isoniazid, C. Pyrazinamide, D. Ethambutol
A: Rifampicin
Answer: A: Rifampicin 
Explanation: Ans. is 'a' i.e., Rifampicin o Isoniazid is bacteriostatic for resting bacilli, but is bactericidal for rapidly dividing microorganisms. -- G & G o The bactericidal action of rifampicin covers all subpopulations of TB bacilli.