External intercostals are located between the ribs and assist inhalation.

External intercostals are located between the ribs and assist inhalation.

• A. They are between ribs and assist inhalation.
• B. They are between ribs and assist exhalation.
• C. They wrap around the bone.
• D. They are in the abdominal wall.

Answer: (A)

The main idea is understanding where the external intercostal muscles are and what they do in breathing. These muscles lie between adjacent ribs, and when they contract they lift the ribs upward and outward. This expands the thoracic cavity, increases lung volume, and lowers intrathoracic pressure, drawing air into the lungs. So they assist inhalation. That’s why the statement that they are between ribs and assist inhalation is the best fit. They don’t wrap around the bone, they aren’t located in the abdominal wall, and assisting exhalation would point to other muscles (like internal intercostals or abdominal muscles), not the external intercostals.

The main idea is understanding where the external intercostal muscles are and what they do in breathing. These muscles lie between adjacent ribs, and when they contract they lift the ribs upward and outward. This expands the thoracic cavity, increases lung volume, and lowers intrathoracic pressure, drawing air into the lungs. So they assist inhalation.

That’s why the statement that they are between ribs and assist inhalation is the best fit. They don’t wrap around the bone, they aren’t located in the abdominal wall, and assisting exhalation would point to other muscles (like internal intercostals or abdominal muscles), not the external intercostals.