Every week, Jade spends her allowance on half a pound of sour lemon gummy candies even though they always make her mouth water. One day, as she is walking down the street, Jade sees a girl carrying a little white bag that looks like a candy shop bag! Jade notices that her mouth is puckering and overflowing with saliva. In this example, the unconditioned stimulus is the .

Sour lemon gummy candy.

Explanation:

Classical conditioning is the form of learning when the neutral stimulus with the unconditioned stimulus results in the strong biological response. Pavlov explains the classical conditioning.

The unconditioned stimulus is the stimulus that has the ability to naturally triggers a particular response. On seeing gummy candies, the salivation begins in mouth and acts as the unconditioned stimulus. This response is not learned and present automatically.

Thus, the answer is sour lemon gummy candy.

Homologous organs can be described as structures having the same internal organization.

The forelimbs of many vertebrates have the same arrangement of bones. Some of these vertebrates having similar organisation of forelimbs are bird wings, bat wings, flippers, and human arms and legs.

Although the function of these limbs yet they have similar internal organisation.

A bird's wing helps the bird in flying. Bat wing helps the bat to fly. Human arm and legs are used for movement. Flippers help in movement in water.