This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Misc., Subject name: Microbiology
[{'content': 'The acid fast staining characteristic of Mycobacteria appears to be due to which of the following cell wall constituent \nSelect and explain. \nA. Mycolic acid, B. Lipopolysaccharide, C. Lipid A, D. N-acetyle muramic acid', 'role': 'user'}, {'content': "Answer: A \nExplanation: (A) Mycolic acid # Acid fastness is attributed to the organisms' high content of mycolic acids, long chain cross-linked fatty acids and other cell wall lipids.", 'role': 'assistant'}]