When nitrogenous waste accumulates in the blood, it indicates a malfunction in the organ responsible for its removal. Option 1, the liver, is not the correct answer because the liver plays a role in detoxification, but it does not directly remove nitrogenous waste. Option 2, the lungs, is also not the correct answer because although the lungs are involved in gas exchange, they do not directly eliminate nitrogenous waste. Option 4, the heart, is not the correct answer because the heart is responsible for pumping blood and does not directly participate in the elimination of waste products. The correct answer is option 3, the kidneys. The kidneys are responsible for filtering the blood and removing nitrogenous waste, such as urea and creatinine, through the production of urine.