Intellectual disability refers to the disability of the mental functions which are characterised by the low or limited approach to thinking, learning, reasoning and the problem solving abilities.
The intellectual disability also involves the limitations in the adaptive behaviour which interfere with the social learning and skills.
The etiology term is used by the doctors to know the origin of the way the things are now. The etiological perspective fro intellectual disabilities therefore is the result of wither the biological defects in the brain or some disease.
Thus, Etiological perspective is the correct answer.
The answer is facilitated diffusion. Facilitated diffusion happens when there is a
carried changing the cell membrane so the nutrients can pass through. During facilitated diffusion, the absorbed
nutrients such as water soluble vitamins need a specific carrier to transport
the to the cell membrane.