Answer:
E. that area of the membrane is in the absolutely refractory period.
Explanation:
Refractory period is a period during which neuron cell cannot be stimulated (depolarized). This is why the action potential can only travel in one direction from the neuron body towards axon.
Refractory period occurs because of the inactivation of voltage-gated sodium channels (while action potential is at its peak) which cannot be open for a certain period of time. and membrane cannot be depolarized.