Which of the following happens during inhalation?

During inhalation, the diaphragm and external intercostal muscles between the ribs contract, increasing the size of the thorax. This decreases the air pressure in the lungs. Because air moves from an area of higher pressure to an area of lower pressure, air is drawn into the lungs. Upon exhalation, the diaphragm and external intercostal muscles relax, the thorax decreases in size, and the air pressure in the lungs increases, pushing air out of the lungs.