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': 'Medium term intervention for Vitamin A prophylaxis is – \nSelect and explain. \nA. Measles immunization, B. Vit A supplementation, C. Fortification of food, D. Green leafy vegetables', 'role': 'user'}, {'content': 'Answer: C \nExplanation: None', 'role': 'assistant'}]