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
The receptors for parathyroid hormone are present in: 
Select and explain. 
A. Osteoblasts, B. Osteoclasts, C. Periosteum, D. Cartilage
A: Osteoblasts
Answer: A: Osteoblasts 
Explanation: None