choice-point

After asking a question here about when exactly a Redo is called in Prolog with new variables, or when it is attempted with the same, I thought I figured it out. In the following piece of code, however, I thought that an additional Redo were to be called, but that does not seem to be the case. My knowledge base is the following: location(desk,office). location(apple,kitchen). location(flashlight,desk). location('washing machine',cellar). location(nani,'washing machine'). location(broccoli,kitchen). location(crackers,kitchen). location(computer,office). edible(apple). edible(crackers). My query