This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Endocrinology, Subject name: Pediatrics
[{'content': 'Central precocious puberty in a girl is defined as breast development before the age of? \nSelect and explain. \nA. 6 years, B. 8 years, C. 12 years, D. 10 years', 'role': 'user'}, {'content': "Answer: B \nExplanation: b. 8 years(Ref: Nelson's 20/e p2656, Ghai 8/e p 534)Central precocious puberty is defined by onset of breast development before the age of 8 yrs in girls and by onset of testicular development (vol 4mL) before the age of 9 yrs in boys, as a result of early activation of hypothalamic-pituitary-gonadal axis.", 'role': 'assistant'}]