Final answer:
The best description for pulmonary hypertension is huge, dilated pulmonary arteries, which reflects the condition where pulmonary arterial pressure is elevated, leading to dilation and changes in the arterial walls.
Step-by-step explanation:
The best description of pulmonary hypertension would be C. Huge, dilated pulmonary arteries (PA). Pulmonary hypertension is a type of elevated blood pressure that affects the arteries in the lungs and the right side of the heart. In advanced stages, this condition can lead to the enlargement and dilation of the pulmonary arteries as a compensatory mechanism to cope with increased resistance within the pulmonary circulation.
Pulmonary hypertension occurs when the pressure in the blood vessels leading from the right side of the heart to the lungs is too high. As the condition progresses, the increased pressure can cause changes in the walls of the pulmonary arteries, leading to thickening and stiffening, thus making the arteries dilated and less efficient at transporting blood. The right side of the heart must work harder to pump against these elevated pressures, which can eventually lead to right heart failure.