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
Osteoblasts express which of the following hormone: 
Select and explain. 
A. PTH., B. Vitamin D3., C. Glucocorticoid., D. All of the above.
D: All of the above.
Answer: D: All of the above. 
Explanation: Other than these hormones, estrogen is also expressed by osteoblasts receptors.