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': 'The following statements are true with reference to Mycoplasma except - \nSelect and explain. \nA. They are the smallest prokaryotic organisms that can grow in cell free culture media, B. They are obligate intracellular organisms, C. They lack a cell wall, D. They are resistant to Beta-lactam drugs', 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]