**Core Concept**
Vesicoureteric reflux (VUR) is a condition characterized by the abnormal flow of urine from the bladder back into the ureters or kidneys, leading to potential complications such as urinary tract infections (UTIs) and renal scarring. Accurate diagnosis is crucial for managing this condition effectively.

**Why the Correct Answer is Right**
Micturating cystography (MCUG) is a specific radiological procedure that involves filling the bladder with a contrast agent through a catheter and then taking X-rays during urination. This allows for direct visualization of the bladder and ureters, enabling the diagnosis of vesicoureteric reflux. The contrast agent helps to highlight the flow of urine from the bladder to the ureters, making it possible to identify any reflux. MCUG is considered the gold standard for diagnosing VUR, especially in pediatric patients.

**Why Each Wrong Option is Incorrect**
**Option B:** X-ray abdomen is not sufficient for diagnosing VUR as it does not provide detailed images of the bladder and ureters, and it does not involve the use of contrast agents.

**Option C:** CT (Computed Tomography) scan of the abdomen with contrast (CECT Abdomen) can provide detailed images of the urinary tract but is not typically used for diagnosing VUR due to radiation exposure and high costs.

**Option D:** Intravenous pyelography (IVP) involves injecting a contrast agent into a vein, which is then excreted by the kidneys and visualized on X-rays. While IVP can provide information about the kidneys and ureters, it is not specific for diagnosing VUR.

**Clinical Pearl / High-Yield Fact**
It is essential to note that the diagnosis of VUR in children often involves a combination of clinical evaluation, laboratory tests, and imaging studies. A thorough understanding of the symptoms and signs of VUR, such as recurrent UTIs and kidney scarring, is crucial for clinicians to make an accurate diagnosis.

**✓ Correct Answer: A. Micturating cystography**