**Core Concept**
The diagnosis of appendicitis involves clinical evaluation and imaging studies to confirm the inflammation of the **appendix**. The **Alvarado score** is a clinical scoring system used to diagnose acute appendicitis, considering symptoms such as **migration of pain** and signs like **tenderness**.

**Why the Correct Answer is Right**
Since the options are not provided, let's discuss a common confirmatory test for appendicitis. Imaging studies like **computed tomography (CT)** or **ultrasound** can confirm appendicitis by showing an enlarged appendix.

**Why Each Wrong Option is Incorrect**
**Option A:** Without the specific option, we cannot determine its incorrectness.
**Option B:** Similarly, without the option, its incorrectness cannot be explained.
**Option C:** This option's incorrectness also cannot be determined.
**Option D:** The same applies to this option.

**Clinical Pearl / High-Yield Fact**
A key point to remember is that **appendicitis** typically presents with **initial diffuse or generalized abdominal pain** that **migrates to the right lower quadrant**, and confirmation often involves a combination of clinical judgment and imaging.

**Correct Answer:** D. CT scan of the abdomen