This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Anti-Leprotic, Subject name: Pharmacology
True about lepra bacilli is 
Select and explain. 
A. INH inhibits their growth, B. Antileprosy vaccine can give life long protection, C. Mycobacterium leprae can be grown in foot pad of mice, D. Incubation period is 3-4 months
C: Mycobacterium leprae can be grown in foot pad of mice
Answer: C: Mycobacterium leprae can be grown in foot pad of mice 
Explanation: Ans. is 'c' i.e., Mycobacterium leprae can be grown in foot pad of mice Mycobacterium leprae - Incubation period -Leprosy has a long incubation period, an average of 3-5 years of more for lepromatous cases. The tuberculoid leprosy has a shorter incubation period.Culture -M. Leprae can be cultured in footpad of mice. In fact it is the only certain way to identify mycobacterium leprae. It is 10 times more sensitive at detecting M leprae than are slit Skin smears.Drugs effective against M leprae - RifampicinDapsone - QuinoloneClofazimine - MinocyclineEthionamide and protionamide - ClarithromycinINH has no role in the t/t of M leprae. It is highly effective against M. Tuberculosis.Anti leprosy vaccineSeveral 'candidate' vaccines have been tried against M. leprae but none of them have attained (Vaccinehood9 as yet.The most effective vaccine against M. Leprae is BCG vaccine + heat killed M. leprae Also know-Globi are characteristic of lepromatous leprosy.They are actually macrophages stuffed with Lepra bacilli and they form clumps.