**Core Concept:** Aortic stenosis is a valvular heart disease characterized by a narrowing of the aortic valve orifice, leading to reduced blood flow from the left ventricle to the aorta and ultimately the systemic circulation. This can cause symptoms like chest pain and signs like multiple non-ejection clicks on auscultation.

**Why the Correct Answer is Right:** Aortic stenosis is often referred to as a "graded" valvular heart disease because its severity can be assessed by measuring the pressure gradient across the narrowed aortic valve. The correct answer, **D** - echocardiogram, is a non-invasive imaging technique that can visualize the aortic valve and measure the pressure gradient. Echocardiography can determine the severity of aortic stenosis, which is essential for tailoring the treatment strategy.

**Why Each Wrong Option is Incorrect:**

A. **Coronary angiography (CAG)** is an invasive procedure that involves injecting contrast medium into the coronary arteries to visualize their lumen. It is not relevant for diagnosing aortic stenosis, which is a valvular heart disease.

B. **Chest X-ray (CXR)** is a radiological examination that provides general information about the heart size and positioning but lacks the resolution to diagnose aortic stenosis.

C. **TTE (Trans-thoracic echocardiography)** is a type of echocardiography that uses ultrasound waves for imaging. Although TTE is a valuable tool in detecting valvular heart diseases, it is not specific for diagnosing aortic stenosis.

**Clinical Pearl:** The presence of multiple non-ejection clicks on auscultation is a clinical clue to aortic stenosis, but the definitive diagnosis requires echocardiography, specifically B-mode and Doppler echocardiography to measure the pressure gradient across the narrowed aortic valve and assess the severity of the disease.

**Explanation of the question:**

A patient named Chandani presents with chest pain and auscultatory findings of multiple non-ejection clicks. The task is to identify the appropriate diagnostic test to confirm the suspicion of aortic stenosis.

**Correct Answer Explanation:**

Echocardiography, specifically B-mode and Doppler echocardiography, is necessary to confirm the clinical suspicion of aortic stenosis. This examination will demonstrate the narrowing of the aortic valve (stenosis) and the associated pressure gradient which helps in assessing the severity of the disease.

**Why the other options are incorrect:**

CXR and TTE are valuable tools for cardiac imaging but are not specific for aortic stenosis diagnosis. Coronary angiography (CAG) is an invasive cardiac procedure to visualize the coronary arteries and not relevant for a valvular heart disease assessment.