Why Is the Loss of Myelin in Multiple Sclerosis a Problem

Why is the loss of myelin in multiple sclerosis a problem?

A) The compensatory increase in sodium (Na⁺) channels can lead to nervous system overexcitation.
B) The spike-initiation zone moves too far away from the cell body to conduct an action potential.
C) The reduced number of calcium channels leads to less neurotransmitter release.
D) There are too few sodium channels in the previously myelinated axon to conduct an action potential.