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: Medicine
[{'content': 'Red cells are caught as innocent bystanders in the reaction between drug and antibodies against that drug, and develops hemolysis. Which drug is responsible for such a reaction? \nSelect and explain. \nA. Penicillin, B. Sulfonamide, C. Naphthalene, D. Primaquine', 'role': 'user'}, {'content': "Answer: A \nExplanation: After exposure red cells can be caught as innocent bystanders during the reaction between penicillin and antipenicillin antibodies. Ref: Harrison's principles of internal medicine, 18th edition, Page 881.", 'role': 'assistant'}]