Which of the following does not happen during inspiration?

During inspiration, the diaphragm contracts and moves downward, the intercostal muscles between the ribs contract, causing the ribs to move up and out, and the thoracic cavity increases in size, which results in a decrease in internal air pressure, allowing air to rush into the lungs. Therefore, the option that does not happen during inspiration is "Diaphragm relaxes". During inspiration, the diaphragm contracts and flattens, increasing the volume of the thoracic cavity and causing air to flow into the lungs. When the diaphragm relaxes, it moves back up into its dome-shaped position, decreasing the volume of the thoracic cavity and causing air to flow out of the lungs during expiration.