This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Pubey and Adolescent Health, Subject name: Pediatrics
[{'content': 'At the onset of pubey the testicular size reaches? \nSelect and explain. \nA. 2 ml, B. 4 ml, C. 8 ml, D. 12 ml', 'role': 'user'}, {'content': 'Answer: B \nExplanation: At the onset of pubey the testicular size reaches 4 ml volume or 2.5 cm length.', 'role': 'assistant'}]