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: Pharmacology
[{'content': 'Allergic reactions depends on all except \nSelect and explain. \nA. Previous exposure to the drug, B. Dosage of the drug received, C. Pharmacological action of the drug, D. Antigen antibody reaction', 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]