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': 'Primary level of prevention means: March 2013 (g) \nSelect and explain. \nA. Effos are directed towards discouraging children from adopting harmful lifestyles, B. Action taken prior to the onset of disease, which removes the possibility that a disease will ever occur, C. Action which halts the progress of a disease at its incipient stage and prevents complications, D. All measures available to reduce or limit impairments and disabilities, minimize suffering caused by existing depaures from good health', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Ans. B i.e. Action taken prior to the onset of disease, which removes the possibility that a disease will ever occur', 'role': 'assistant'}]