Which One of the Following Steps Occurs During the Absolute

Multiple Choice

Which one of the following steps occurs during the absolute refractory period?

A) The neuron cannot generate an action potential.
B) Sodium channels open, releasing sodium ions into the neuron, which causes potassium channels to close.
C) Sodium channels open, which causes potassium channels to open.
D) A nerve impulse fails to reach threshold.
E) Potassium channels open, releasing potassium ions from the neuron; sodium channels close.