This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Infection, Subject name: Medicine
Multi-drug resistance tuberculosis implies resistance to at least - 
Select and explain. 
A. Any two antitubercular drugs, B. Isoniazid and ethambutol, C. Rifampicin and ethambutol, D. Isoniazid and rifampicin
D: Isoniazid and rifampicin
Answer: D: Isoniazid and rifampicin 
Explanation: Multidrug-resistant TB is defined by resistance to atleast rifampicin & isoniazid, with or without other drug resistance . Extensively drug resistant TB is defined as resistance to atleast rifampicin & isoniazid in addition to any quinolone & atleast one injectable second -line agent. Reference: Harrison20th edition pg 1056