How to protect drop down menus in google sheet?

I want to make a google sheet, where multiple users can select a value from a drop down menu, and not do anything else (like adding other values, deleting content etc.).

I have made this solution with data validation (4 options, color coded). All good, but: if I protect the cells, users can't enter data. If I do not protect the cells, users can actually delete the content of the cell (the drop down menu disappears).

Any other/smarter way to do this?