This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Miscellaneous (E.N.T.), Subject name: ENT
[{'content': 'An edentulous patient had carcinoma of the oral cavity infiltrating into the lower alveolar margin. All the following are possible treatment options except: \nSelect and explain. \nA. Segmental mandibulectomy, B. Marginal mandibulectomy with removal of outer table, C. Radiotherapy, D. Commando', 'role': 'user'}, {'content': 'Answer: C \nExplanation: (c) Radiotherapy(Ref. Cummings, 6th ed., 1372)Since radiation to the mandible carries risk of osteoradionecrosis, carcinoma lower alveolus/ mandible is dealt with surgically in all the stages.Chemotherapy may be given in T3 T4 tumours.', 'role': 'assistant'}]