If You Record EPSCs with a Patch Electrode from an Interneuron

Multiple Choice

If you record EPSCs with a patch electrode from an interneuron in the
CA1 region of a rat hippocampal slice preparation and hold the postsynaptic membrane potential at -80 mV, why is the response not sensitive to blockers of NMDA receptors?

A) There are no NMDA receptors at these synapses.
B) At -80 mV, AMPA receptors are blocked by magnesium.
C) At -80 mV, NMDA receptors do not bind glutamate.
D) At -80 mV, NMDA receptors are blocked by magnesium.
E) At -80 mV, NMDA receptors do not bind glycine or D-serine.