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: Surgery
[{'content': "The ideal timing of radiotherapy for Willm's tumor after surgery is - \nSelect and explain. \nA. Within 10 days, B. Within 2 weeks, C. Within 2 months, D. Any time after surgery", 'role': 'user'}, {'content': "Answer: A \nExplanation: The postoperative radiotherapy in Wilm's tumor is started within 10 days of surgery.\nDelay in starting radiotherapy beyond ten days leads to tumor cells repopulation and increases the relapse rate.", 'role': 'assistant'}]