Which system includes the kidneys, ureters, bladder, and urethra?

• A. Urinary
• B. Digestive
• C. Endocrine
• D. Reproductive

Answer: (A)

The function being tested is the system that filters blood and eliminates liquid waste from the body. The kidneys remove wastes and extra water to form urine, the ureters carry that urine to the bladder for storage, the bladder holds it until it’s convenient to urinate, and the urethra is the passage through which urine leaves the body. This coordinated set of organs is the urinary (also called the excretory) system, which helps regulate water and electrolyte balance and maintain proper pH. The other systems handle different roles—digestion processes food and solid waste, the endocrine system uses hormones, and the reproductive system manages reproduction—so the collection of organs listed fits best with the urinary system.