b) The powder was an unconditioned stimulus (UCS) because it was naturally capable of causing the response.
c) Over time, the bell became a conditioned response (CS); it did not initially cause salivation, but the dogs learned to associate the bell with the meat powder and began to salivate at the sound of the bell only.
d) The drooling of these canine consumers over a sound, now linked to feeding time, was a conditioned response (CR).