Answer: By providing antigens, with an inactive virus, to alert the body to create antibodies (white blood cells). So that the body becomes immune to the virus over time.
Explanation: <em>Let's pretend you're a scientist and all -</em> think about how a vaccine works. What do they contain, and why? How does our body react to a vaccine? It helps to think about a time <em>you've</em> possibly had your shots done.
Vaccines contain inactive bacteria or viruses that, when injected, tell our bodies there is an illness. This is known as the antigen. This alerts our body's immune system and as a response, our bodies release white blood cells known as antibodies to fight the illness.
After reading this, reread the passage to get an understanding of how you will write your answer. Good luck!
