How do vaccines give immunity to infectious diseases?

A. They kill pathogenic microbes.

B. They produce an immune response.

C. They contain antibodies against pathogens.

D. They inhibit the antigen-antibody reaction.

B. They produce an immune response.

Vaccines protect you by preparing your immune system to recognize and fight serious, and sometimes deadly, diseases. A vaccine contains a specific part of a germ (bacteria or virus), called an antigen. The antigen is killed or disabled before it's used to make the vaccine, so it can't make you sick.