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': 'What is /are components of Nutrition surveillance? \nSelect and explain. \nA. Policy maker, B. DOTS, C. Nutritional survey, D. AFP surveillance', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Nutrition surveillance: – Main strategy: Detection of malnutrition (nutritional survey)\n– Approach: Diagnostic-interventional\n– Sample: Representative, 50 - 100 size group\n– Objectives: 1. To aid health and development 2. To provide input for program management and evaluation (to policy makers) 3. To give timely warning and intervention (to prevent short-term food crises)', 'role': 'assistant'}]