In an Experiment Studying Classical Conditioning,a Tone Sounds and 5

Multiple Choice

In an experiment studying classical conditioning,a tone sounds and 5 seconds later a mild skin shock is delivered to a participant.The skin shock results in a stress response consisting of a temporary increase in heart rate.This process is repeated once every 5 minutes.After a number of trials,the participant demonstrates an elevated heart rate when the tone sounds and before the shock is actually delivered.Within the context of this example,what is the US?

A) the shock
B) the tone
C) the stress
D) the time interval