Transmission of impulses along a neuron in the vertebrate nervous system ordinarily occurs in only one direction because, following passage of an action potential, the neuron is temporarily in a refractory period or hyperpolarized. this is caused by which answer choice?

The correct answer would be - the potassium ions continue to move out of the axon.

Explanation:

During transmission of the impulse when sodium channels are closed and potassium channels are open, the cell membrane of the axon cell becomes hyperpolarized due to the continuous movement of the potassium ion to outside the axon. During this refractory period, the impulse can not be fire or generated.

Thus, the correct answer would be - the potassium ions continue to move out of the axon.

a and c are the answeres