Movement in and Out of the Lungs Is Controlled Mainly

Movement in and out of the lungs is controlled mainly by which of the following actions?

A) Changes in the pleural pressure and deep abdominal relaxation of the rectus abdominus
B) Downward and upward motion of the diaphragm and elevation and depression of the ribs to increase the diameter of the chest cavity
C) Alveolar contraction and contractions of the heart, circulating blood through the lung anatomy
D) Changes in atmospheric pressure within the respiratory cavities and relaxation of abdominal musculature