Circulatory system
Excretory system
Reproductive system
Respiratory system
Answer is Wrong!
Answer is Right!
The correct answer is B. Excretory system.
Nephrons are the functional units of the kidney. They are responsible for filtering the blood and producing urine. Urine is a waste product that contains water, salts, and other waste products. The kidneys also help to regulate blood pressure and produce hormones that are involved in red blood cell production.
The circulatory system is responsible for transporting blood throughout the body. The reproductive system is responsible for producing offspring. The respiratory system is responsible for exchanging oxygen and carbon dioxide with the environment.
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