This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Immunology, Subject name: Microbiology
[{'content': 'Polysaccharide antigens are: \nSelect and explain. \nA. T cell independent antigens, B. T cell dependent antigens, C. MHC I dependent antigens, D. MHC II dependent antigens', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Ans. (a)For proteins and erythrocytes - T cell dependent antigens.For polysaccharides - T cell independent antigens.Protein antigens eliminated in days to weeks whereas polysaccharide antigens persist for months to years e.g., pneumococcal polysaccharide may persist upto 20 years in humans following a single injection.', 'role': 'assistant'}]