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: Gynaecology & Obstetrics
[{'content': 'Early hormonal sign of puberty \nSelect and explain. \nA. Sleep associated increase in LH, B. Early morning rise in temperature, C. Increased FSH to LH ratio, D. Elevated adrenal androgens.', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Early sign of puberty is Sleep-associated increase in LH secretion.', 'role': 'assistant'}]