**Question:** Which of the following is false about duplication of ureter?

A. Ureter is a single tube that carries urine from kidneys to bladder in humans
B. Duplication of ureter occurs in 10% of cases due to genetic mutations
C. Ureteral reflux is a condition where urine flows from bladder to kidney instead of ureter
D. The ureteral orifice is located at the apex of the bladder neck

**Correct Answer: C. Ureteral reflux is a condition where urine flows from bladder to kidney instead of ureter.**

**Core Concept:** Duplication of ureter is a rare congenital anomaly where the ureteral bud forms two separate tubes during embryonic development. In most cases, this results in no clinical significance and is detected incidentally during imaging studies or surgery.

**Why the Correct Answer is Right:** Ureteral reflux is not a condition where urine flows from the ureter to the kidney, but rather it is a condition where urine flows from the bladder to the kidney against the normal flow direction. This can lead to complications such as renal parenchymal disease, hypertension, and renal failure.

**Why Each Wrong Option is Incorrect:**

A. The statement that the ureter is a single tube carrying urine from the kidney to the bladder is correct, as it is a crucial part of the urinary system in humans.

B. Duplication of ureter is a rare phenomenon and does not affect the majority of individuals. It is only relevant in a limited number of cases and does not apply to the correct answer about ureteral reflux.

D. The correct answer about ureteral orifice location at the apex of the bladder neck is important in understanding the anatomy of the urinary tract. This option is relevant and correct in general, but does not address the specific false statement about ureteral reflux.

**Clinical Pearl:** Ureteral reflux is a potentially serious condition that must be identified and treated promptly to prevent complications. Diagnosis can be made with voiding cystourethrogram (VCUG), renal ultrasound, or renal scintigraphy. Treatment usually involves antireflux surgery or medical management.