Final answer:
The axon terminal is the part of the neuron that transmits messages to the next neuron, and the answer to the question is B. Axon terminal.
Step-by-step explanation:
The end of the axon branch, which transmits messages to the next neuron, is known as the axon terminal. The synapse is the site of communication between neurons, found at each axon terminal, and it is where signals are transmitted to other cells. While the myelin sheath acts as an insulator to speed up signal conduction, and dendrites are the structures that receive signals, it is the axon terminal that is directly involved in transferring the signal to the next neuron.
An axon may branch out several times, with each branch ending in an axon terminal, but each neuron will only have one axon. The axon terminal plays a crucial role in the transmission of nerve impulses through the release of neurotransmitters, which are then received by dendrites of another neuron, thereby facilitating neural communication.
Therefore, the correct answer to the question "The end of the axon branch; its function is to transmit messages to the next neuron" is B. Axon terminal.