**Core Concept**
Pelvic-ureteric junction (PUJ) obstruction is a condition where the flow of urine from the kidney to the bladder is blocked due to a narrowing or obstruction at the junction of the ureter and the renal pelvis. This can lead to renal damage and impairment if left untreated.

**Why the Correct Answer is Right**
The correct answer will be related to a statement that is not true about PUJ obstruction. PUJ obstruction is often caused by a congenital anomaly, such as a crossing vessel or a ureteral fold, which can lead to an increase in ureteral pressure and subsequent renal damage. The obstruction can be diagnosed using imaging studies, such as intravenous pyelography (IVP) or computed tomography (CT) scans, which can show a dilated renal pelvis and ureter.

**Why Each Wrong Option is Incorrect**
* **Option A:** This option may state that PUJ obstruction is always caused by a congenital anomaly, which is not true. While congenital anomalies are a common cause of PUJ obstruction, they are not the only cause. Acquired causes, such as kidney stones or tumors, can also lead to PUJ obstruction.
* **Option B:** This option may state that PUJ obstruction always presents with flank pain, which is not true. While flank pain is a common symptom of PUJ obstruction, it is not a universal symptom. Some patients may be asymptomatic or present with only mild symptoms.
* **Option C:** This option may state that the treatment for PUJ obstruction is always surgical, which is not true. While surgical correction is often necessary to treat PUJ obstruction, some cases may be managed conservatively with medications or lifestyle modifications.
* **Option D:** This option may state that PUJ obstruction is only seen in children, which is not true. While PUJ obstruction is more common in children, it can also occur in adults, often as a result of an acquired cause.

**Clinical Pearl / High-Yield Fact**
PUJ obstruction can lead to chronic kidney damage and impairment if left untreated. It is essential to diagnose and treat PUJ obstruction promptly to prevent long-term renal damage.

**Correct Answer: A. This option may state that PUJ obstruction is always caused by a congenital anomaly, which is not true. While congenital anomalies are a common cause of PUJ obstruction, they are not the only cause.**