Which correctly compares the immunity produced by a vaccine with the immunity produced by injection of antibodies from an external source? Injection of antibodies helps the body develop memory cells, which only produces a temporary immunity, whereas a vaccine can fight infection for years. A vaccine helps the body develop memory cells that make immunity last, whereas injection of antibodies only produces a temporary immunity. Injection of antibodies helps the body develop its own copies of the antibodies so immunity lasts, whereas a vaccine only produces a temporary immunity. A vaccine actively attacks pathogens until it is used up so immunity is temporary, whereas injected antibodies will remain passively in the blood, giving immunity for life.