Concept:The kidney is the main organ responsible for regulating water balance in the body.
Explanation:The lungs remove carbon dioxide and some water vapour during breathing.
The skin removes water, salts, and wastes through sweating.
The large intestine removes solid waste and a small amount of water in feces.
The kidneys filter the blood and excrete excess water, urea, and salts as urine.
Because urine contains the largest volume of excess water, the kidney removes more water than any other organ.
Answer:Kidney (Option C)