Q: Fact 1: Nephrons are the structural and functional units of the kidneys. Fact 2: Normally the kidneys manufacture urine. Given the two facts above, nephrons are the structural and functional units of what?

Choose from: (A). Something coming from a gland (B). A compound that donates proton (C). urine manufacturing organs (D). Veins and arteries. (E). critical organs (F). sensory neurons (G). food and shelter (H). the body's largest organ
A:
(C).