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': 'Which of the following tests is the least useful in endodontic diagnosis of children? \nSelect and explain. \nA. Percussion, B. Palpation, C. Electric pulp test, D. Cold test', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Electric pulp testL\xa0Until apical closure occurs, teeth do not respond normally to electric pulp testing. In addition, a traumatic injury may temporarily alter the conduction capability of nerve endings and/or sensory receptors in the pulp. A patient with a vital pulp may not experience any sensation right after trauma.', 'role': 'assistant'}]