This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Communicable diseases, Subject name: Social & Preventive Medicine
[{'content': 'True statement about plague is - \nSelect and explain. \nA. Vaccine is not used to control epidemic of pneumonic plague, B. Most impoant measure to control epidemic rodent control, C. Septicemic plague is highly infectious, D. Live attenuated vaccines are used', 'role': 'user'}, {'content': "Answer: A \nExplanation: - the most efficient method to prevent plaque is control of rat flea. -immunisation with plaque vaccine is a valuable preventive measure. The WHO recommends that under all circumstances, vaccination should be used only for the prevention not the control of human plaque. - killed plaque vaccine is used. Reference : Park's textbook of preventive and social medicine, 23rd edition pg no:296 <\\p>", 'role': 'assistant'}]