The correct answer is multiple sclerosis.
The MS or multiple sclerosis refers to a demyelinating disorder in which the insulating envelopes of the nervous tissues in the spinal cord and the brain get destructed.
This destruction disturbs the tendency of the components of the nervous system to interact, leading to an array of symptoms and signs, involving mental, physical, and on certain occasions psychiatric issues.
<h2>
It may become endangered </h2>
Explanation: <u><em>If organisms cannot adapt to the changes in their ecosystem, they may move to another location. If they will not move, the species may become threatened, endangered, or extinct. Under an evolutionary phenomenon called relaxed selection, traits that were advantageous in one time and place become obsolete in another. Traits that aren't actively maintained by natural selection tend to become smaller or less functional over time, studies suggest.</em></u>
Is also decreasing with respect to time!
