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': 'The primary cause of acantholysis in pemphigusvulgaris is \nSelect and explain. \nA. auto immunity, B. intercellular oedema, C. intra epithelial oedema, D. chronic alcoholism', 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]