Dear student,
Answer: Liver.
Heart is the organ that serves to pump the blood which in turn carries substances with it. Kidneys and skin are the excretory organs of body that serve to remove the waste substances from the body. Kindeys serve in removal of nitrogenous waste in form of urine. Skin serves to remove the waste products along with sweat out of the body. But, liver is not involved in movement of substances.
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