<prompt> Acute infection of hepatitis B virus is diagnosed by:IgM antibody of Hbs AgIgM antibody of Hbc AgIgG antibody of Hbs AgIgG antibody of Hbc Ag  <response>: Ans. is b IgM antibody of HBcAg Ref. November 2001, Micro, Harrison 17e p 1943-44,1933-34 16e, p 1823-24. 