This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Papulosquamous disorders, Subject name: Dental
[{'content': "'Twenty-nail syndrome' is seen in \nSelect and explain. \nA. Darier's disease, B. Lupus vulgaris, C. Lichen planus, D. Psoriasis", 'role': 'user'}, {'content': 'Answer: C \nExplanation: Nail involvement occurs in 10% of individuals with disseminated lichen planus, and nail lesions may be the only manifestation and can destroy the nails. One, several, or all 20 nails may be involved ("twenty-nail syndrome," where there is loss of all 20 nails without any other evidence of lichen planus elsewhere on the body Twenty-nail dystrophy is a condition that affects the nails of the fingers and toes. This condition most commonly occurs in childhood, but it can occur at any age. Ref: Harrison 20th edition pg 1223', 'role': 'assistant'}]