This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: mycology, Subject name: Microbiology
[{'content': 'Black coloured grains in mycetoma is produced by \nSelect and explain. \nA. Leptospira, B. Nocardia, C. Actinomadura, D. Phaecremonium', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Leptospira, madurella, exophiala produce black colored colonies or grains in mycetoma Nocardia-white Phaecremonium -yellowish white Ref: Baveja 5th ed pg: 551', 'role': 'assistant'}]