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: Pathology
[{'content': 'Formation of multiple pinpoint bleeding spots on scratching the skin is characteristic of: \nSelect and explain. \nA. Pemphigus vulgaris, B. Lupus erythematosus, C. Psoriasis, D. Herpangina', 'role': 'user'}, {'content': 'Answer: C \nExplanation: None', 'role': 'assistant'}]