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: Skin
[{'content': 'Most characteristic Feature of lichen planus is: \nSelect and explain. \nA. Thinning of nail plate is most common, B. Non scarring alopecia, C. Violaceous lesions on skin and mucous membrane, D. Wickham striae', 'role': 'user'}, {'content': 'Answer: D \nExplanation: D i.e. Wickham Striae', 'role': 'assistant'}]