Nowadays every newborn gets regular shots of vaccine for polio. It contains _ for polio to make a child immune against this disease.

Explanation

A vaccine elicits an immune response by the host so that the host is better equipped to fight against the invading organism, in any potential future instance, via the production of memory cells. It may do so by containing the antigens of the invading organism (in this case, poliovirus) so that the host's immune system produces memory cells against the specific organism, thereby conferring active immunity against the disease. Antibiotics (option A) are not present in vaccines; they are drugs used to treat bacterial illnesses. Antibodies (option B) are not present in vaccines; they are proteins, produced by plasma cells, to ward off infection. They are produced by the immune system to fight an active infection, but they are not used in vaccines since they do not confer active immunity as the host does not produce memory cells against the invading organism. Antisera (option D) is a blood serum preparation that contains antibodies against a certain antigen or disease; they are used as a treatment for certain conditions and do not confer active immunity to the individual.