What is the function of the 'tail -f' command?

The 'tail -f' command is used to monitor a file for new lines being added in real-time. This is particularly useful for observing log files or any other file that changes frequently. When you execute this command, it opens the specified file and displays the last few lines, then continues to "follow" the file as it grows. Every time a new line is added to the file, it prints that line to the terminal. This functionality is essential for tasks like monitoring the output of applications, tracking system logs, or debugging, as it allows users to see updates immediately without needing to refresh or repeatedly check the file manually.

The other options do not accurately describe the purpose of 'tail -f'. The command does not show the first few lines of a file, measure file size, or remove lines from a file. Therefore, the correct description of 'tail -f' is its capability to provide a live view of new content being appended to a specified file.