What anatomical structure connects the kidneys to the bladder?

The correct answer is the ureters, which are the anatomical structures that connect the kidneys to the bladder. Each kidney has a ureter that transports urine from the renal pelvis of the kidney to the urinary bladder for storage before it is expelled from the body. This transport is facilitated by peristaltic movements of the smooth muscle in the ureter walls, which help push the urine downward toward the bladder.

The renal pelvis is a funnel-shaped structure within the kidney itself that collects urine before it enters the ureter, but it does not connect directly to the bladder. The urethra is the duct through which urine is expelled from the bladder to the outside of the body; it does not connect the kidneys to the bladder. The nephron is the functional unit of the kidney that filters blood and produces urine, but it is not a structure that connects the kidneys to the bladder. Understanding these distinctions clarifies why the ureters are the correct choice for this question.