<prompt> Polysaccharide antigens are:T cell independent antigensT cell dependent antigensMHC I dependent antigensMHC II dependent antigens  <response>: Ans. aFor 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. 