Question

a firewall is a _________.
group of software programs that runs autonomously on zombie computers
software program or hardware device designed to protect computers from hackers
program deployed by hackers that looks at each packet as it travels on the internet
program that allows hackers to gain access to a persons computer and take almost complete control
i dont know yet

Explanation:

A firewall is a security measure that can be software or hardware, designed to monitor and control incoming/outgoing network traffic to protect systems from unauthorized access (e.g., hackers). The other options describe malicious tools (like botnets, packet sniffers used by attackers, or remote access trojans), not firewalls.

Answer:

software program or hardware device designed to protect computers from hackers