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': 'Cell wall structure is found in all except ? \nSelect and explain. \nA. Staph aureus, B. Pseudomonas aeruginosa, C. Mycoplasma pneumoniae, D. Corynebacterium diphtherae', 'role': 'user'}, {'content': "Answer: C \nExplanation: Ans. is 'c' i.e., Mycoplasma pneumoniae", 'role': 'assistant'}]