When neurotransmitter molecules bind to receptors in the plasma membrane of the receiving neurona. ion channels in the plasma membrane of the sending neuron open. b. ion channels in the plasma membrane of the receiving neuron open. c. the receiving neuron becomes more negative inside. d. the receiving neuron becomes more positive inside. e. vesicles in the synaptic terminal fuse to the plasma membrane of the sending neuron.

b. ion channels in the plasma membrane of the receiving neuron open.

d. the receiving neuron becomes more positive inside.

and e. vesicles in the synaptic terminal fuse to the plasma membrane of the sending neuron.

Explanation:

When a neurotransmitter molecule binds to a receptor in the plasma membrane of a receiving neurona the vesicles in the presynaptic terminal that are carrying neurotransmitters  will fuse to the plasma membrane of the sending neuron freeing its content in the synaptic cleft. Once that the neurotransmitters are in the synaptic cleft they will bind with the ion channels in order to open them. When the channels are open the ions will start entering the post synaptic cell, in this case the neurona,  making the inside of the neurona more positive and producing an action potential.