At an Excitatory Synapse, an Action Potential in the

At an excitatory synapse, an action potential in the

A) postsynaptic neuron depolarizes the presynaptic cell membrane.
B) presynaptic neuron increases the permeability of the subsynaptic membrane of the postsynaptic cell to both Na⁺ and K⁺.
C) presynaptic neuron increases the permeability of the subsynaptic membrane of the postsynaptic cell to K⁺ only.
D) both (a) and (b) above.
E) both (a) and (c) above.