Answer
Correct answer is d. Active immunity can be produced by having a disease as well as by getting a vaccine containing killed or attenuated pathogenic organisms that cause that disease. In either case, a n active immune response is triggered when mature/ activated immune cell meet their specific antigen.
Gammaglobulins are antibodies produced by plasma B-cell/plasma cells when they encounter their specific antigen. Gammaglobulins injected into an organism/person that does not have them will confer immunity, but it is passive immunity and it is temporary immunity.
Work Step by Step
For active immunity to be produced, immune cells must learn to recognize their specific antigen, encounter and react to it, and retain the ability to mount subsequent attacks on said specific antigen because of the information retained in memory cells. Immunity conferred by gammaglobulin injections is passive immunity, it can be effective, but it is temporary immunity. Babies get gammaglobulins from their mothers through the placenta and from breast milk. But such immunity at best lasts a few months to a about 12 months. So babies should vaccinated. Whereas, passive immunity to whooping cough and influenza Type B(HiB) may protect babies for only about two months ( if the mother had the antibodies in her blood), passive immunity to measles. mumps and rubella my still be protective up to a year after birth.
