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': 'A 34 years old person has rapidly developing cough, dyspnoea, expectoration and blood tinged sputum. He is febrile, cyanosed, and toxic. Chest examination reveals crepitations and ronchi. The mostlikely diagnosis is: \nSelect and explain. \nA. Legionella, B. Pneumonic plague, C. Septicemic plague, D. Pulmonary tuberculosis', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Pneumonic plague', 'role': 'assistant'}]