Concept:Excretion is the removal of metabolic waste from the body. The kidneys are the primary excretory organs in humans.
Explanation:The kidneys filter the blood to remove urea, excess water, and excess salts.
These wastes are concentrated into urine, which is then eliminated from the body through the urinary system.
The liver assists by converting harmful ammonia into urea, but it does not excrete waste directly.
The lungs expel carbon dioxide and some water vapour, which is only a minor excretory function.
The pancreas is mainly involved in digestion and hormone production, not waste removal.
Because the kidneys perform the greatest share of waste filtration and removal, they are the organs primarily responsible for excretion in humans.
Answer:C. Kidneys