IPSPs (inhibitory postsynaptic potentials) a. block the efflux of potassium ions. b. are local hyperpolarizations. c. are local depolarizations. d. block the efflux of calcium ions. e. increase membrane permeability to sodium ions.

IPSPs are local hyperpolarizations.

Option B

Explanation:

The Inhibitory Post Synaptic Potentials are basically resultant of local hyper polarization and by then they degrade to depolarization. These are synaptic potentials which causes the neuron of post synapse to engage in lesser generation of action potential.

The local hyper polarization is achieved as the post synapse membrane has the negative potential more than that of resting membrane, then the condition becomes hyper polarization. In order to achieve so, the action potential must under go depolarization and hence it degrades to depolarization.