This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Urinary tract, Subject name: Pathology
[{'content': 'Subepidermal blisters with granular deposits of IgA selectively localized to the tips of dermal papillae is a feature of- \nSelect and explain. \nA. Dermatitis herpetiformis, B. Pemphigus vulgaris, C. Lichen planus, D. Psoriasis vulgaris', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Histologically, the early lesions of dermatitis herpetiformis consist of neutrophilic micro-abscesses at the tips of papillae, producing separation or blister between the papillary dermis and the epidermis. The older blisters contain a fair number of eosinophils causing confusion with bullous pemphigoid. Direct immunofluorescence shows granular deposits of IgA at the papillary tips in dermatitis herpetiformis. Ref: Textbook of pathology by Harshmohan 6th edition page 777.', 'role': 'assistant'}]