Armadillos curl up into a ball when attacked. reginald teaches an armadillo to curl up into a ball when a buzzer sounds. reginald is making use of the phenomenon known as

The term that best fits the blank provided is PREPAREDNESS. When Reginald taught armadillos to curl up into a ball when attacked through a buzzer sound, he is using the phenomenon which is known as preparedness. The armadillos prepare themselves once they are triggered by the said stimulus.