Receptor sites for neurotransmitters are present on Membranes of synaptic vesicles, Pre-synaptic membrane, Tips of axons, Post-synaptic membrane

Neurotransmitters are the chemicals that help to transfer the nerve signal from one neuron to the other during chemical synapse. These are stored in the synaptic vesicles at the axon terminal. These are released across the synaptic cleft, where they bind to specific receptors located on the postsynaptic side of the synapse. So, the correct answer is option A.