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: Microbiology
[{'content': 'T helper cells recognizes - \nSelect and explain. \nA. MHC class I, B. MHC class II, C. Processed peptides, D. Surface Ig', 'role': 'user'}, {'content': 'Answer: B \nExplanation: MHC restriction\n\nT cells (in contrast to B cells) cannot be activated by soluble antigens.\nTherefore, presentation of processed antigen by antigen presenting cells is required for induction of cell mediated immunity.\nT cell receptors recognizes peptide antigens that are displayed by major histo compatibility complex (MHC) molecules on the surface of antigen presenting cells.\nT cells develop MHC restriction so that :-\n\n\nHelper (CD4) T cells respond only to foreign antigens presented along with HLA class II (MHC class II).\nCD8 T cells respond to antigens presented along with HLA class I (MHC class I).\nMHC restriction refers to the fact that a given T cell will recognize a peptide antigen only when it is bound to a particular MHC molecule.', 'role': 'assistant'}]