This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Mycobacterial Infections, Subject name: Dental
[{'content': 'In leprosy neural involvement occurs in what percentage of patients \nSelect and explain. \nA. 30%, B. 60%, C. 90%, D. 100%', 'role': 'user'}, {'content': 'Answer: D \nExplanation: A chronic granulomatous disease caused by Mycobacterium leprae, principally affecting peripheral nerves and skin. Nerve involvement is seen in all cases of leprosy. The cardinal signs are: 1. Hypopigmented/hypoanaesthetic patches 2. Peripheral nerve thickening 3. Skin slit smear(AFB).', 'role': 'assistant'}]