This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Tumours of skin, Subject name: Dental
[{'content': 'A 78-year-old retired farmer shows you the lesion below, which he has noticed on his arm. What would be the most appropriate management of this lesion? \nSelect and explain. \nA. Cryotherapy, B. Watchful waiting, C. Excision biopsy, D. Shave biopsy', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Keratin horns should be excised fully including the base to allow the histological exclusion of an underlying squamous cell carcinoma. Cryotherapy will not provide a tissue for histology and Curettage or shave biopsy may yield insufficient depth for diagnosis.', 'role': 'assistant'}]