Which muscles are located between the ribs and are involved in the process of ventilation?

The intercostal muscles are found between the ribs and play a vital role in the process of ventilation, which is the movement of air in and out of the lungs. These muscles contract and expand the thoracic cavity, facilitating inhalation and exhalation. During inhalation, the external intercostal muscles elevate the ribs, increasing the volume of the thoracic cavity and allowing air to be drawn into the lungs. Conversely, during exhalation, the internal intercostal muscles can assist by pulling the ribs downward, which decreases the volume of the thoracic cavity and helps push air out of the lungs.

Other muscle groups mentioned in the options have different functions relating to bodily movement or respiration. The serratus muscles primarily facilitate the movement of the shoulder blade rather than directly participating in ventilation. The diaphragm also contributes significantly to breathing; however, it is not located between the ribs. Instead, it is a large, dome-shaped muscle at the base of the thoracic cavity. The rectus abdominis, a major abdominal muscle, plays a role in forceful exhalation but is not involved in the mechanical process of ventilation in the same direct manner as the intercostal muscles.