Answer:
C. Kidney
Explanation:
The kidney is a vital organ in the human body. It is bean shaped and helps in the filtration of toxic substances and wastes from the body fluids which is then reabsorbed into the bloodstream.
The kidney also controls the level of water, pH and sodium levels. It however controls the blood pH by excretion of hydrogen ions and forming bicarbonate which ensures the blood pH is within its optimal and normal range.
