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': 'Which of the following is used to treat Paroxysmal nocturnal hemoglobinuria ? \nSelect and explain. \nA. Eculizumab, B. Avelumab, C. Natalizumab, D. Sarilumab', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Eculizumab is monoclonal antibody against C5 complement used in the treatment of paroxysmal nocturnal hemoglobinuria.', 'role': 'assistant'}]