Injecting a person with a vaccine that is made from a dead or weakened virus can
protect that individual from the disease because -

A: live bacteria later prey on them instead of live tissues.

B: the vaccine increases muscle tissue which makes you stronger.

C: the body builds an immune response, which helps fight future exposure to the
same virus.

D: it gives the person a mild form of the disease, which conditions the body not to
respond to later infection.