Q.52 A vаccine thаt оnly cоntаins purified pоlysaccharide antigens generates a response that is NOT dependent on T-lymphocyte control. As a result, there is no immunoglobulin class switching during the immune response. In this setting, 2 months after vaccination with purified polysaccharides which of the following immunoglobulin classes will most likely be the only (or nearly the only) class present?