Excel

It depends on exactly what you want and which version of Excel and where the file is located/shared.
For example the 'traditional' way might be to use VBA/macro to run on open to detect user or prompt for user and then perform show/hide actions.
But macros are now blocked on the new excel in sharepoint (you can use local excel and allow macros if you security setting are set accordingly), but you could add a button for them to press that runs a script to peform some showing/hiding.
Either way is not as easy as a quick formatting setting.
Alternatively, I could suggest WorksheetA, WorksheetB, WorksheetC for users A,B,C and each worksheet is formatted accordingly and the cell just reference the needed values in WorksheetMaster. Then on open the users might be prompted with a 'There are external links, shoud values be updated?' type of prompt but then it will be formatted and showing the correct information for each corresponding user.