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: Orthopaedics
[{'content': 'Most common lesion of the mandible is- \nSelect and explain. \nA. Ameloblastoma, B. Squamous cell ca, C. Osteosarcoma, D. Osteoclastoma', 'role': 'user'}, {'content': 'Answer: A \nExplanation: "Ameloblastoma is the most common jaw tumour" -- Radiology of head & Neck\n"Ameloblastoma is the most common tumour of the maxillomandibular region. The mandible is affected in 75% of cases,\xa0the maxilla in 25%". -- Oral pathology', 'role': 'assistant'}]