Question: Marge is assisting her client to increase the duration of their daily workouts. Marge collects initial baseline data and is ready to begin implementing the intervention. When setting up her design, Marge divides her treatment phase into stepwise subphases, setting each subphase with a different required number of minutes during daily workouts for her client to meet. Marge varies the number of sessions she runs with her client for each subphase, sometimes running three session in a subphase, five sessions in the next subphase, seven session is next subphase, back to five in the next and so on, to see how closely responding matches regardless of how long the client remains in a subphase. Which consideration is Marge addressing when using a changing criterion design? Randomizing the order of conditions Selecting the appropriate degree of criteria change Enhancing discriminability Varying lengths of phases