Which of the following commands will display the last 30 lines of /var/log/bigd.log as well as new content as it is appended to the file by another process?

The `cut` command is used for extracting sections from lines of files and does not have options to display last lines or follow file content.

The `head` command displays the *first* lines of a file, not the last, and the `-e` option is not a standard way to follow file content.

The `tail` command is used to display the end of a file. The `-n 30` option specifies to show the last 30 lines, and the `-f` (follow) option keeps the command running, continuously outputting new data that gets appended to `/var/log/bigd.log` by another process, which is ideal for real-time log monitoring.

The `tac` command prints lines in reverse order, and `taC.30` is not valid syntax for displaying last lines or following a file.

The `cat` command concatenates and displays entire file contents and lacks options to show only the last lines or to follow appended content.