Innate defenses counter specific disease-causing agents, whereas adaptive defenses include mechanical and chemical barriers:

Kidneys are not part of the lymphatic system.

The lymphatic system is a network of vessels and organs that drain excess fluid from the tissues, transport fats and immune cells, and protect the body from infections.

Kidneys are part of the urinary system, which filters blood, regulates fluid and electrolyte balance, and produces urine.

Choice A is wrong because kidneys do not have a direct connection to the lymphatic system.

Although kidneys have lymphatic vessels in their cortex, they do not originate from the lymphatic system.

Kidneys receive blood from the renal arteries and return it to the renal veins.

The lymphatic vessels in the kidney cortex drain interstitial fluid and immune cells from the kidney tissue to the regional lymph nodes.

Some additional sentences are:

Choice B is right because kidneys are part of the urinary system, not the lymphatic system.

The urinary system and the lymphatic system have different functions and structures in the body.

Normal ranges for kidney function tests include blood urea nitrogen (BUN) of 7 to 20 mg/dL, serum creatinine of 0.6 to 1.2 mg/dL, and glomerular filtration rate (GFR) of more than 90 mL/min/1.73 m.

Normal ranges for lymphatic system tests include white blood cell (WBC) count of 4,000 to 11,000 cells per microliter, lymphocyte count of 1,000 to 4,800 cells per microliter, and immunoglobulin levels of IgG (700 to 1,600 mg/dL), IgA (70 to 400 mg/dL), IgM (40 to 230

mg/dL), IgE (0 to 100 IU/mL), and IgD (0.5 to 5 mg/dL).

Excretion is the process of removing metabolic wastes or excrements from the body.
Metabolic wastes are substances left over from metabolic processes (such as cellular respiration) which cannot be used by the organism and must therefore be excreted.
These include nitrogen compounds, water, CO2, phosphates, sulphates, etc.
Choice B. Absorption is wrong because absorption is the process of taking in substances into the body or cells.
It is not related to the removal of waste.
Choice C. Metabolism is wrong because metabolism is the sum of all the chemical reactions that occur in an organism.
It is not a process of removing wastes, but rather producing them.
Choice D. Assimilation is wrong because assimilation is the process of incorporating substances into the body or cells.
It is also not related to the removal of waste.
Normal ranges for metabolic wastes vary depending on the type and concentration of the waste, as well as the organism and its environment.
For example, ammonia is a very toxic waste that requires a lot of water for its excretion, while uric acid is a less toxic waste that can be concentrated into a small volume.
Some normal ranges for human metabolic wastes are:

Urea: 2.5 to 6.4 mmol/L in blood serum Uric acid: 3.4 to 7.2 mg/dL in blood serum Creatinine: 0.6 to 1.2 mg/dL in blood serum CO2: 35 to 45 mmHg in arterial blood gas