This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Bacterial Infection of Skin, Subject name: Skin
[{'content': 'Two ulcers on the chest wall and axilla, associated with underlying sinus tracts and discharge. Diagnosis? \nSelect and explain. \nA. Lupus vulgaris, B. Scrofuloderma, C. Lichen scrofulosorum, D. TBVC', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Ans. B. ScrofulodermaScrofuloderma (also known as "Tuberculosis cutis colliquativa") is a skin condition caused by tuberculous involvement of the skin by direct extension, usually from underlying tuberculous lymphadenopathy.', 'role': 'assistant'}]