Answer:
The answer would be, C) Firewall
Step-by-step explanation:
We can eliminate antivirus, because it helps to protect the file system against unwanted programs not from hackers. We can also eliminate routers because it helps you connect multiple devices to the Internet, and connect the devices to each other. A router won't keep a hacker away from important files, thus has nothing to do with protection. And last but not least, peer-to-peer networks. Peer-to-peer networks is one in which two or more PCs share files and access to devices such as printers without requiring a separate server computer or server software. So that definitely won't help.
Hope this helped! Have a great day! - Olli :]