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': 'A child of 5 year age reported to the clinic with fracture of deciduous incisor that is involving the pulp, it is considered as \nSelect and explain. \nA. Ellis class 1, B. Ellis class 2, C. Ellis class 3, D. Ellis class 9', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Trauma to primary teeth is included in Ellis class 9 fracture.', 'role': 'assistant'}]