locking down rows, not columns or sheets


Hi guys, we have a scenario where we would like to lock down the rows of a sheet depending on the criteria in a given column; for example if category a is selected then people x,y and z can make changes, if category b is selected then only persons l,m,n can make changes and so on. This is because everyone needs to be able to see the resulting reports, but only certain people should be changing certain rows.

Does anyone know if there is a way to do this?