Answer:
If a US occurs just as often without the tone as it does in the presence of the tone, then little or no conditioning will accrue to the tone. This would suggest that animals are sensitive to _____ of the potential CS and US. the correct answer for this excercise is: "Contingency"
Step-by-step explanation:
To understand this answer we first have to remember contingency's concept and then analyze the context.
First, contingency in behavioral psychology is the link/ bond established in the interaction of a certain response and the frequency, regularity, and level of reinforcement for that response. Thus, in this case, we can figure out that the text is about how the difference of tone in the stimulus would determine if the establishment of conditioning is effective or not based on its format. Because a tone variation would suggest different stimuli.