1. Break down of Food into Energy
Oxygen
2. Absorb X - Rays in Bones
Calcium
3. Cell Membrane Function
Sodium
4. All Organic Compounds
Carbon
The answer is amyloid beta. They clump together and form plaques. The formed plaque can block signals transmitted from one cell to another cell. In addition, the plaque can cause swelling, especially in the area where it is formed. It can also digest the disabled cells. This type of plaque is very common among patients with Alzheimer's Disease.
I think you are right. B is the right answer.
That is when extinction occurs. Hope I helped!