[dba-Tech] Outlook 2010 check

If you're using Outlook 2010, would you mind checking something for me? Using the Customize Ribbon feature (File tab | Options), can you delete the Reply All option under Respond for the Home (Mail) tab? Mine is dimmed, so I can't do anything -- won't let me delete it. But, it doesn't make sense that it'd be in the list, if I can't actually manipulate it in any way. 

If your's isn't dimmed, let me know, please. 

If you know why mine is dimmed, please let me know. 

Thanks!
Susan H.