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': 'Myospasm that is involuntary continuous contraction of a muscle due to overstretching which is already strained\nbecause of sustained mouth opening during RCT is \nSelect and explain. \nA. Charley horse, B. Ercess expand, C. Muscle tear, D. Hardy stretch', 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]