You are presented with the question "nephrons are the structural and functional units of what?" and the following answer choices: 
- Something coming from a gland
 - A compound that donates proton
 - urine manufacturing organs
 - Veins and arteries.
 - critical organs
 - sensory neurons
 - food and shelter
 - the body's largest organ

Now knowing that nephrons are the structural and functional units of the kidneys and normally the kidneys manufacture urine, choose the best answer.


 

   urine manufacturing organs      