How can you display the contents of a text file in the terminal?

To display the contents of a text file in the terminal, the correct command is cat filename.txt. The cat command, short for "concatenate," is widely used in the Linux environment to read and display the content of files directly to the terminal. When you execute this command, the terminal reads the specified file and outputs its content to the screen, allowing users to view it quickly.

The other commands listed do not serve this purpose in a standard Linux environment. For example, show, display, and open are not standard commands used to read text files in the terminal. They may belong to other utilities or environments, but they do not function as expected in basic Linux command line operations for displaying file contents. Thus, the adoption of cat makes it the most effective and widely recognized method for this task in Linux.