Which Statement Is True

question 127

Multiple Choice

Which statement is true?

• A) There is little polymorphism at MHC loci in humans.
• B) Cytotoxic T cell receptors recognize antigenic fragments only when they are bound to class II MHC molecule.
• C) T-helper cells have a surface protein that binds to antigen‒class I MHC complexes.
• D) Cytotoxic T cells use a protein called CD8 to ensure binding to an MHC-antigen complex.
• E) T-helper cells bind to pathogens that display cell surface antigens.

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