Which one of the following antimicrobial drugs is suitable for treatment of both tuberculosis and leprosy?

Rifampicin is a powerful broad spectrum antibiotic that is a core component of both Multi Drug Therapy for leprosy and the standard treatment regimen for tuberculosis. While Isoniazid and p aminosalicylic acid are primarily used for tuberculosis and have limited effect on leprosy, and Streptomycin is an injectable antibiotic used mainly for tuberculosis, Rifampicin is highly effective against both Mycobacterium tuberculosis and Mycobacterium leprae. It works by inhibiting the bacterial RNA polymerase, preventing the pathogens from synthesizing proteins. Therefore, it is the common drug used in the global standard treatment for both diseases.