How does this process protect you from getting sick from the virus?
this is talking about the process of vaccine.

A vaccine is a preparation of a weakened or killed pathogen such as a bacterium or virus, or a portion of the pathogen's structure  that upon administration to an individual, stimulates antibody production or cellular immunity against the pathogen.

The adaptive arm of the immune system produces memory cells that  store memory of the pathogen e.g. virus that was used for the vaccine. When that same type of virus is encountered a second time, the memory cells remember it and trigger a very rapid,  strong and well coordinated attack on the virus, effectively neutralizing and destroying it.

the correct answer is 4 (giveaways to the public)

something that is given away or gave out for free. an occasion at which things are given away to free. something that is evident or obvious; something that uncovers a mystery.

it could be be in a form of a lucky draw as well. these the company events gather more audience for their pr and it also increases their ratings as well. this is a way to attract more customers towards themselves.

answer; /// i believe the answer is (sterilization ) plz check first.good luck