This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Concept of health and disease, Subject name: Social & Preventive Medicine
[{'content': 'Secondary prevention is applicable to \nSelect and explain. \nA. Casual factors, B. Early stage of disease, C. Late stage of disease, D. General population', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Secondary prevention includes early diagnosis and treatment, so it aims at preventing a disease progressing to complications Ref: Park&;s textbook of preventive and social medicine; 23rd edition; Pg no: 42', 'role': 'assistant'}]