Answer:
Option (1).
Step-by-step explanation:
Multiple sclerosis may be defined as the medical condition in which the individual may lose the ability to walk and think. The brain and spinal cord get damaged in the multiple sclerosis.
The oligodenedrocytes that are involved in the formation of myelin sheath of the central nervous systrem are lost. This might result in the absence of myelin sheath and impairs the saltatory conduction. The speed of the transmission of the nerve impulse decreases.
Thus, the correct answer is option (1).