Which command can be used to restore a deleted file?

Restoring a deleted file in Linux typically depends on the context of the file deletion and the specific methods of file management being used. The command that is often associated with file recovery, particularly in the context of using backup systems, is not listed among the options.

The restore command, which might seem intuitive, is actually specific to certain backup systems like the dump utility and is not a universal or standard command for general file restoration on Linux systems. Similarly, recover and unrm are not standard commands in most Linux distributions.

When a file is deleted in Linux, it is often removed from the filesystem index, and unless recovery mechanisms such as backups or specialized recovery tools are in place, the file cannot be easily restored through standard terminal commands. The absence of any valid command in the provided options to perform a general file restoration leads to the conclusion that none of the available choices would effectively restore a deleted file in a typical scenario.

Thus, the most appropriate answer is that none of the presented options can be used to restore a deleted file, highlighting the importance of backing up data and understanding the limits of command-line utilities in file management.