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: Social & Preventive Medicine
[{'content': 'Recommended dose of anti-rabies serum to be given for passive immunization of adult victim of dog bite is \nSelect and explain. \nA. 20 i.u., B. 40 i.u., C. 60 i.u, D. 80 i.u.', 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]