Drop Down Menu, checking path of entries

Hi,
I have made a test spreadsheet with a 3 tier drop down menu. These drop down menus have several different bits of data in each tier, each leading to a dependent drop down. Therefore I thought it may be useful for me to have a "Check Path" box, in which the user could type any of the data entries and it would tell them what they'd need in each drop down menu to get to it. I have attached the file, and was wondering if anyone could offer any suggestions how to do this. Thanks.