Answer
(a) it hyperpolarizes the postsynaptic membrane
Work Step by Step
Binding of neurotransmitters at inhibitory synapses reduces a postsynaptic neuron’s ability to generate an AP. Most inhibitory neurotransmitters hyperpolarize the postsynaptic membrane by making the membrane more permeable to K+ or Cl-. This change in membrane permeability hyperpolarizes the postsynaptic membrane.