## **Core Concept**
The patient's symptoms and physical examination findings suggest a condition affecting the heart valves, specifically causing obstruction to blood flow. The presence of exertional angina and syncope in conjunction with a systolic ejection murmur radiating to the carotids points towards aortic stenosis. Aortic stenosis is a valvular heart disease characterized by the narrowing of the aortic valve opening, which obstructs blood flow from the left ventricle to the aorta.

## **Why the Correct Answer is Right**
The correct answer, **C. Aortic Stenosis**, is the most likely diagnosis due to the combination of symptoms and physical examination findings presented:
- **Exertional Angina**: This occurs because the stenotic valve cannot open widely enough to accommodate increased cardiac output during exercise, leading to ischemia.
- **Syncope**: This can happen due to the inability of the stenotic valve to allow adequate blood flow to the brain during exertion or changes in posture.
- **Systolic Ejection Murmur with Radiation to the Carotids**: This type of murmur is classic for aortic stenosis. The murmur is due to turbulent blood flow across the stenotic valve.
- **Soft S2**: This indicates that the valve is stenotic and not closing properly, which is consistent with aortic stenosis.

## **Why Each Wrong Option is Incorrect**
- **Option A: Mitral Regurgitation**. This condition typically presents with a pansystolic murmur radiating to the axilla, not a systolic ejection murmur radiating to the carotids. It can cause heart failure symptoms but not typically exertional angina and syncope as primary presentations.
- **Option B: Pulmonary Stenosis**. While this can cause a systolic ejection murmur, it usually does not radiate to the carotids. The murmur of pulmonary stenosis is often associated with findings related to right heart disease.
- **Option D: Hypertrophic Cardiomyopathy (HCM)**. HCM can cause exertional syncope and angina. However, the murmur associated with HCM is typically a dynamic murmur that can vary with maneuvers and does not characteristically radiate to the carotids.

## **Clinical Pearl / High-Yield Fact**
A key clinical pearl is that the classic triad of symptoms for aortic stenosis includes **exertional angina**, **syncope**, and **dyspnea**. However, not all patients present with all three. The physical examination finding of a systolic ejection murmur radiating to the carotids, coupled with a soft S2, is highly suggestive of severe aortic stenosis.

## **Correct Answer: C. Aortic Stenosis**