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': 'Testis tumor is associated with secondary hydrocele in \nSelect and explain. \nA. 1% of cases, B. 10% of cases, C. 20% of cases, D. 30% of cases', 'role': 'user'}, {'content': 'Answer: B \nExplanation: • Approximately 5-10% of testicular tumors may be associated with hydroceles.', 'role': 'assistant'}]