<prompt> Epstein-Barr virus causes autoimmunity by:Molecular mimicryInducing inappropriate expression of class H MHCRelease of sequestere antigensPolyclonal B cell activation  <response>: Ans. d Polyclonal B-cell activation EBV receptor CD-21 on the surface of B-cells is also the receptor for the C3d component of complement. So, when B-cells are infected with EBV they become transformed and can proliferate indefinitely. This polyclonal activation of B-cells leads to the production of antibodies directed against host cells and viral proteins. Thus, this is also not difficult to understand that cellular immunity is more impoant than humoral immunity in controlling EBV infection. 