Hi Abhijeet ,
Sorry , but you need to understand it yourself.
This technique modifies an individual component of a .xlsx file ; a .xlsx file is actually an archive of several files , some of which are .xml files , and these are the ones used to store customizations of the Ribbon.
In future , if you wish to disable some other menu item on the Ribbon using this same technique , you will again have to resort to the xml editor ; it is better if you can spend some time to understand this so that you can do it yourself.
Narayan