The binding of a neurotransmitter on a postsynaptic cell allows potassium ions to diffuse out of the cell. this would result in a which is an event.

The binding of a neurotransmitter on a postsynaptic cell allows potassium ions to diffuse out of the cell. This would result in a NEGATIVE CELL MEMBRANE POTENTIAL which is an HYPERPOLARIZATION event.

Explanation:

The binding of a neurotransmitter to a postsynaptic cell results in a group of channels in the cell membrane called ligand gated channels open or close in response to that binding.

Hyperpolarization occurs when a ligand gated channel opens and allows potassium ion to flow out of the cell.

During hyperpolarization, potential of the cell membrane experience changes which makes it to become more negative.