This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Identification, Subject name: Forensic Medicine
[{'content': "Gustafson's method used for age estimation of tooth includes all except - \nSelect and explain. \nA. Primary dentition, B. Root resorption, C. Root transparency, D. Attrition", 'role': 'user'}, {'content': 'Answer: A \nExplanation: Gustafsons method uses attrition, periodontosis, secondary dentin, cementum apposition, root resorption and transparency of root to determine age of adult from dentition. Ref: Dr.Narayana Reddys Synopsis of Forensic Medicine & Toxicology 27th edition pg. 36.', 'role': 'assistant'}]