Keeping track

Hi folk

is it possible to use excel to keep track of things e.g

a list of vehicles....

3 headings. Operational. Waiting repair. In garage

in a cell under the headings, insert an X and the cell turns green with the other two remaining blank, however when you select the cell under another heading that turns green and the original goes blank

Thanks

Here is one option (see encl. file).
I hope it is enought to get started.
//Ola

another way included (remove validation if you dont want it)