Final answer:
Neurotransmitters are chemical messages that allow neurons to communicate with each other.
Step-by-step explanation:
The correct answer is neurotransmitters. These are chemical messages that allow neurons to communicate with each other. They are released from the terminal vesicles of one neuron and bind to receptors on another neuron, transmitting the signal. Examples of neurotransmitters include dopamine, serotonin, and acetylcholine.
Learn more about neurotransmitters