$ sudo apt-get remove file-preseed 

Uninstall file-preseed including dependent package

If you would like to remove file-preseed and it's dependent packages which are no longer needed from Ubuntu,

$ sudo apt-get remove --auto-remove file-preseed 

Use Purging file-preseed

If you use with purge options to file-preseed package all the configuration and dependent packages will be removed.

$ sudo apt-get purge file-preseed 

If you use purge options along with auto remove, will be removed everything regarding the package, It's really useful when you want to reinstall again.

$ sudo apt-get purge --auto-remove file-preseed 

See Also,