Answer: Option B
:
B
Depolarization of a nerve cell membrane occurs during the passage of an action potential along the axon where the nerve is transmitting an impulse. During depolarization, the Voltage-gated Na⁺ channels open, and Na⁺ rush into the axon. Entry of sodium ions leads to depolarization (reversal of polarity) of the nerve membrane. This membrane depolarization causes the opening of voltage-gated K⁺channels, allowing K⁺ions to exit and repolarization of the membrane.