Although hunger naturally occurs in response to an empty stomach, we can easily become conditioned to feel hunger at certain times of the day due to classical conditioning. in this case, the us would be the

a. empty stomach.

b. food.

c. time of day.

d. eating.

The answer to this question would be
 a. empty stomach. 
Hunger naturally caused by the decreased blood glucose level, so eating sugar will lessen it. But it also can be induced by an empty stomach. There is a receptor in the stomach that detect whether it is a stretch (mean that there is something inside it). Lack of stretch can cause it to send a signal that will result in hunger.Explanation:
you've most likely practised gnawing, painful feelings in your abdomen at some purpose, in the higher left aspect of your abdomen. These are usually referred to as hunger pangs. Hunger pangs, or hunger pains, are caused by sturdy contractions of the abdomen once it’s empty. This uncomfortable sensation is usually among hunger, or the will to eat.

Despite being known as “hunger” pangs, these pains don’t continuously indicate a really got to eat.

The answer to this question would be a. empty stomach. 

Hunger naturally caused by the decreased blood glucose level, so eating sugar will lessen it. But it also can be induced by an empty stomach. There is a receptor in the stomach that detect whether it is a stretch (mean that there is something inside it). Lack of stretch can cause it to send a signal that will result in hunger.