Biology

The correct answer is: B.Synaptic vesicles.

Neurotransmitters are stored in synaptic vesicles, which are located at the nerve terminal of a neuron. When an electrical signal (action potential) reaches the synapse, the vesicles fuse with the cell membrane and release neurotransmitters into the synaptic cleft, allowing communication between neurons or between neurons and other types of cells (like muscle cells).

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