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': 'Richest source of vitamin I is - \nSelect and explain. \nA. Milk, B. Egg, C. Green leafy vegetables, D. Fish oil', 'role': 'user'}, {'content': "Answer: D \nExplanation: Ans. is 'd' i.e., Fish oil", 'role': 'assistant'}]