How does a vaccine work?
a. it kills viruses.
b. it protects cells from viral infection.
c. it prepares the immune system to recognize viruses.
d. it prevents viruses from being transmitted from an infected person.

Basically all a vaccine is would be cells from the virus that is injected into you but the catch is the virus has been altered to prepare your immune system for what is to come if you catch the original virus so the correct answer would be C hope this is helpful for you.