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: Physiology
[{'content': 'Which of the following hormones exerts the least effect on calcium metabolism of bone tissue? \nSelect and explain. \nA. Androgen, B. Estrogen, C. Nor epinephrine, D. Thyroid hormone', 'role': 'user'}, {'content': 'Answer: C \nExplanation: None', 'role': 'assistant'}]