When reviewing file security configurations, a Linux administrator needs to determine if any files in a directory are set with the 'immutable' attribute to prevent alterations. Which command should the administrator use and what flag should they be looking for in the output?
Use the lsattr command and look for files with the 'i' flag
Use the lsattr -a command and search for files with the 'a' flag
Use the lsattr -l command and look for a detailed list of attributes
Use the chattr command to check for the 'i' attribute