Final Answer:
NESSUS, OpenVAS, and Nikto, which Lacks a GUI is c) Nikto
Step-by-step explanation:
Among NESSUS, OpenVAS, and Nikto, Nikto lacks a graphical user interface (GUI). Nikto is a web server vulnerability scanner designed for command-line use. It is primarily used to identify potential security issues and vulnerabilities in web servers and web applications.
Unlike NESSUS and OpenVAS, which offer GUIs for user-friendly interactions, Nikto operates through a command-line interface (CLI). Users input commands to execute scans and obtain results. While NESSUS and OpenVAS provide visual interfaces that facilitate easier navigation and configuration, Nikto relies on text-based commands for its functionality.
In summary, the correct answer is c) Nikto, as it lacks a GUI and is utilized through a command-line interface for web server vulnerability scanning.