<prompt> Adoptive immunity is by:InfectionInjection of antibodiesInjection of lymphocytesImmunization  <response>: Ans. is c i.e., Injection of lymphocytesRef: Jawetz, 27the, p. 130 An extract of immunologically competent T - lymphocytes, known as transfer factor can be used in the treatment of lepromatous leprosy when CMI is low. 