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: Medicine
Which of the following drug is not used for MDR-TB? 
Select and explain. 
A. Amikacin, B. Kanamycin, C. Levofloxacin, D. Ethionamide
A: Amikacin
Answer: A: Amikacin 
Explanation: None