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: Social & Preventive Medicine
[{'content': 'All of the following are killed vaccines, EXCEPT: \nSelect and explain. \nA. Salk, B. Hepatitis B vaccine, C. 17-D Vaccine, D. HDCV', 'role': 'user'}, {'content': "Answer: C \nExplanation: 17-D vaccine is a live attenuated vaccine used to control yellow fever. Killed vaccines are used to control typhoid, cholera, peusis, plague, rabies, salk (polio), influenza, hepatitis A, B, japanese encephaltis and KFD. Ref: Park's Textbook Of Preventive and Social Medicine 20th edition page 98.", 'role': 'assistant'}]