Answer:
B. Synapse
Step-by-step explanation:
The synapse is the space or the communication between two neurons or betwenn a neuron and a muscular cell or a secretory cell. Humans use the chemical synapse. The processes begings with an action potential producing a depolarization openening neurotransmitters (NT) vesicles releaseing calcium allowing the NT allowing the NT to the membrane of the postsynaptic cell sending the signal.