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: Medicine
[{'content': 'Cancer can be prevented by ingestion of - \nSelect and explain. \nA. Beta carotene, B. Vitamin C & E, C. Selenium, D. All the above', 'role': 'user'}, {'content': 'Answer: D \nExplanation: None', 'role': 'assistant'}]