Task: Question Generation
Input (English): Blood delivers oxygen in the body. Proteins and acids are broken down in the liver. The liver releases waste in the form of urea. The blood carries the urea and carbon dioxide to the kidneys. The kidneys strain the urea and salts needed from the blood. The carbon dioxide by product is transported back to the lungs. Carbon dioxide is exhaled by the lungs. 
Output (English): How does blood remove waste from the human body?