This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: RNTCP, Subject name: Social & Preventive Medicine
[{'content': 'All of the following drugs are used in the management of MDR-TB under RNTCP except \nSelect and explain. \nA. Levofloxacin, B. PAS, C. Ethionamide, D. Cycloserine', 'role': 'user'}, {'content': 'Answer: B \nExplanation: PAS is an add-on agent(D GROUP) and is not a core pa of MDR-TB drug regimen. The remaining 3 drugs are being given in both intensive as well as continuation phase of the regimen.', 'role': 'assistant'}]