Netcat, often referred to as the“Swiss Army knife of networking,”is a versatile, open-source tool used for reading from and writing to network connections using TCP or UDP. This makes option B the correct answer. Netcat is widely used in ethical hacking, penetration testing, and system administration due to its flexibility and simplicity.

Netcat can perform a wide range of networking tasks, includingport scanning, banner grabbing, file transfers, reverse shells, bind shells, and debugging network services. It is commonly used during thereconnaissance, exploitation, and post-exploitation phasesof ethical hacking. Because of its ability to create raw network connections, it can simulate both client and server behavior.

Option A and option C are incorrect because Netcat iscross-platformand works on Linux, Windows, macOS, and other Unix-like systems. It is not limited to a single operating system, nor is it exclusively a hacking tool; it is also used legitimately by network administrators for troubleshooting and testing.

From a defensive security perspective, understanding Netcat is important because attackers frequently abuse it to establish unauthorized communication channels or backdoors. Ethical hackers use Netcat responsibly to demonstrate how weak configurations or exposed services can be exploited.

By identifying improper Netcat usage during assessments, organizations can improve monitoring, restrict unnecessary outbound connections, and strengthen endpoint security controls.