This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Introduction, Subject name: Pediatrics
[{'content': 'Antisera is obtained from: \nSelect and explain. \nA. Guinea pig, B. Rabbit, C. Rat, D. Horse', 'role': 'user'}, {'content': 'Answer: D \nExplanation: ANTISERA: -Antisera are usually prepared in horses -provide passive immunization - Immunoglobulin fraction is concentrated using ammonia sulfate & some products are fuher treated with some enzymes to decrease reactions to foreign proteins. -Antisera are used against diseases like Diphtheria, Tetanus, Rabies.', 'role': 'assistant'}]