A progressive disease in which the myelin sheath breaks down overtime without this protective covering nerves cannot conduct impulses to and from the brain in normal way

• A. Memory loss
• B. Mobility
• C. Multiple sclerosis
• D. MSDS

Answer: (C)

The main idea being tested is how loss of myelin affects nerve signaling. Myelin acts as insulation that speeds and coordinates impulses along nerve fibers; when it deteriorates, signals slow down or halt, so messages to and from the brain aren’t conducted normally. Multiple sclerosis is a progressive autoimmune disease that attacks the myelin in the central nervous system, causing impaired conduction and a range of symptoms such as weakness, balance issues, and vision changes. Because the scenario describes the protective covering breaking down and disrupting impulse transmission to the brain, this disease name is the best fit. The other options aren’t diseases: memory loss is a symptom, mobility is a function that can be affected, and MSDS is a safety data sheet unrelated to medical conditions.