Answer:
D
Step-by-step explanation:
Demylination is a neural disease caused due to degradation of myelin or myelination neurons.
This damage impairs the conduction of signals in the affected neurons. This reduction in conduction ability causes deficiency in sensation, movement, cognition and other depending upon the neuron it has affected. In general the The speed of action potential propagation would be slower. Hence option D is the correct answer.