Final answer:
Aortic stenosis can lead to left-sided heart failure and subsequent pulmonary hypertension by causing increased pressure in the left ventricle and atrium due to restricted blood flow through the narrowed aortic valve.
Step-by-step explanation:
Pulmonary hypertension secondary to left-sided heart failure can be caused by conditions that affect the ability of the left side of the heart to move blood efficiently into the systemic circulation. D) Aortic stenosis is a condition that can lead to left-sided heart failure. It causes narrowing of the aortic valve, which can increase the pressure within the left ventricle and subsequently in the left atrium and pulmonary veins, leading to pulmonary hypertension as the blood backs up in the lungs. Aortic stenosis contrasts with A) Pulmonary embolism and B) Chronic obstructive pulmonary disease (COPD), which primarily affect the lungs and right side of the heart. C) Left atrial myxoma, a type of heart tumor, could obstruct blood flow within the heart and potentially lead to increased pressures that contribute to pulmonary hypertension.