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': 'SA-14-14-2- \nSelect and explain. \nA. Deploid cell inactivated, B. Killed vaccine, C. Life long immunity, D. Primary immunization 2 doses', 'role': 'user'}, {'content': "Answer: C \nExplanation: SA 14-14-2 strain is live attenuated vaccine whuch offers life ling immunity.Ref.PARK'S TEXTBOOK OF PREVENTIVE AND SOCIAL MEDICINE 21st edition page no 261", 'role': 'assistant'}]