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: Pediatrics
[{'content': 'Normally, Cortisol levels are maximum at __________ and lowest at ________ \nSelect and explain. \nA. 8 pm and eary morning, B. 12 pm and 12 am, C. 8 am and 8 pm, D. 8 am and midnight', 'role': 'user'}, {'content': 'Answer: D \nExplanation: None', 'role': 'assistant'}]