The stomach normally secretes acid that is essential in the digestive process and this helps in the breaking down of food during digestion. Acidity is responsible for ulcer, dyspepsia, heartburn and the formulation of the ulcer. One way to experiment on how the acid is neutralized is by using vinegar and starch.
The answer is A or the first one
Calcium which is a major mineral in the body
It's the mitochondria, the "powerhouse of the cell".