Which would indicate that a vaccine is protecting a person from future disease?

an increase in antibodies
the production of a fever
the production of phagocytes
an occurrence of inflammation

An increase in antibodies

A Vaccine is a suspension of weakened, killed biological agents like microorganisms, antibodies, lymphocytes that are administered in the body of the infected organisms. The biological agents like bacteria and viruses mimic the disease causing pathogens inside the body and fight with it and provide protection against the disease. It stimulates the immune response in the body and increases the production of antibodies to fight against the disease causing microbes.

A vaccine is protecting a person from future disease indicates that it has increased antibodies in the body.

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