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: Microbiology
[{'content': 'A farmer has an ulcer on the leg with indurated margin and multiple sinuses with discharging granules. The likely diagnosis is - \nSelect and explain. \nA. Mycetoma, B. Scrofuloderma, C. Lupus vulgaris, D. Actinomycosis', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Mycetoma (Maduramycosis)\n\nIs a localized chronic granulomatous involvement of the subcutaneous and deeper tissues, commonly affecting the foot and less often the hand and other parts.\nPresenting as a subcutaneous swelling with multiple discharging sinuses.\nSinuses discharge seropurulent fluid containing granules.\nThese granules are microcolonies of the etiological agents.\nA similar condition called botryomycosis is caused by Staphylococcus aureus.', 'role': 'assistant'}]