Which of the following tools is based on Linux and used to carry out the Penetration Testing?

JPlag is a source code plagiarism detection tool used in academic environments and has no connection to penetration testing.

BackTrack is a Debian/Ubuntu-based Linux distribution specifically designed for penetration testing and digital forensics; it includes a comprehensive suite of tools for network scanning, exploitation, password cracking, and vulnerability assessment, and was the direct predecessor to Kali Linux maintained by Offensive Security.

Vedit is a general-purpose text and hex editor with no security or penetration testing capabilities.

Ettercap is a single network packet sniffer and man-in-the-middle tool that runs on multiple platforms, not a Linux distribution designed as a penetration testing environment.