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': 'Dietary cycle is weighing of raw foods over a period of \nSelect and explain. \nA. 1 day, B. 3 days, C. 7 days, D. 10 days', 'role': 'user'}, {'content': 'Answer: C \nExplanation: None', 'role': 'assistant'}]