Answer:
I'm sorry, but I don't have enough background information to answer this question. Comment when you have updated it.
Explanation:
Explanation:
their: meaning a person or their possession
there: meaning a place
they're: Meaning (they are) mixed together to meaning someone doing a action or describing someone.
Answer:
I am pretty positive its the last one, "How computer viruses can be prevented"
Explanation:
Computer Viruses are the problem, and how they can be prevented is the solution