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': 'All of the following are examples of calcium binding proteins, EXCEPT: \nSelect and explain. \nA. Calmodulin, B. Troponin, C. Calbindin, D. None of the above', 'role': 'user'}, {'content': "Answer: D \nExplanation: Many different Ca2+-binding proteins have been described, including troponin, calmodulin, and calbindin. Ref: Ganong's Review of Medical Physiology 23rd edition, Chapter 2.", 'role': 'assistant'}]