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: Dental
[{'content': 'Within an hour after cementation of cast gold onlay patient complains of shooting pain every time the teeth comes together. Most probable explanation is? \nSelect and explain. \nA. Supraocclusion of restoration, B. Retained cement in gingival sulcus, C. Excess acid in mix, D. Galvanic current caused by gold onlay occluding with a large restoration', 'role': 'user'}, {'content': 'Answer: D \nExplanation: None', 'role': 'assistant'}]