Which of the following describes how kidneys remove nitrogenous waste from the blood

they filter urea from blood and produce urine,

they produce urea and send it to the liver for urine production,

they remove protien remains and produce urea,

they filter the blood for urine and collect it

The correct answer is they filter urea from blood and produce urine.

Nitrogenous wastes tend to form toxic ammonia which needs to be removed. Terrestrial animals must detoxify ammonia by converting it into a relatively nontoxic molecule-urea (it occurs in the urea cycle). The urea cycle mainly occurs in the liver and the produced urea is then released into the blood. It travels to the kidneys where is filtrated and excreted in urine.