Put the events of synaptic transmission in order of their occurrence.
A) Neurotransmitters bind with ligand-gated channels on the postsynaptic membrane.
B) A series of action potentials (electrical signals) trigger the release of neurotransmitters into the synaptic cleft.
C) Calcium ions trigger the fusion of synaptic vesicles with the presynaptic membrane.
D) Action potentials propagate along the axon to the presynaptic terminal.