A blockage in structure a would directly reduce blood flow to the

A blockage in structure A would directly reduce blood flow to the Lungs. The pulmonary artery divides into branches that are parallel to the bronchial tubes and ends in a network of pulmonary capillaries within the walls of the small air passages and alveoli of the lungs. The pulmonary veins carry oxygen-rich blood away from the lungs to the heart.