Ans.
The image below represents neural transduction that involves release of signaling molecules or neurotransmitters by axon terminal of one nerve cell and binding of the released neurotransmitters with the receptors, present on dendrites of another nerve cell. It is method of communication between the neurons. Hence, the image is showing a functional nervous system.
On the other hands, hormones are released by endocrine glands that release their content directly into the blood. The nervous transmission does not include hormone release.
Thus, the correct answer is option C). 'hormone release.'