Rover Gets Fed Whenever His Owner Opens the Refrigerator

Rover gets fed whenever his owner opens the refrigerator.Fluffy gets fed about every third time that her owner opens the refrigerator.Which pet will get most excited when the refrigerator is opened

A)  Rover will, because the open door is a better predictor of food. 
B)  Rover will, because his response will have discriminated more fully. 
C)  Fluffy will, because the feedings have been less predictable and more spontaneous. 
D)  Fluffy will, because the refrigerator door is a more salient cue.