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: Microbiology
[{'content': 'Acid fastness of tubercle bacilli is attributed to - \nSelect and explain. \nA. Presence of mycolic acid, B. Integrity of cell wall, C. Both of the above, D. None of the above', 'role': 'user'}, {'content': 'Answer: C \nExplanation: None', 'role': 'assistant'}]