This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Bacteria, Subject name: Microbiology
[{'content': 'Dark field microscopy is used for - \nSelect and explain. \nA. Syphilic, B. Leprosy, C. Histoplasmosis, D. Capsule', 'role': 'user'}, {'content': "Answer: A \nExplanation: Ans. is 'a' i.e., Syphilic * Dark ground (dark field) microscopy is used for -# Flagella# SpirochetesNote: T pallidum (causative agent of syphilis) is a spirochete.", 'role': 'assistant'}]