Jack, a sixty$-$year$-$old man, is an avid reader. He recently found out the online facility of downloading books. He is happy to have so many options to choose from and to have such easy access to e$-$books. He downloads books from many websites, and he does not mind using unverified websites for downloading them. In this scenario, Jack is most likely to be vulnerable to

firewalls

malware

cybermediaries

cloud computing