Question

multiple choice question
what muscle elevates the rib cage during the inspiration phase of breathing?
internal intercostal
external intercostal
diaphragm

Explanation:

During the inspiration phase of breathing, the external intercostal muscles contract and elevate the rib - cage, increasing the volume of the thoracic cavity. The internal intercostal muscles are mainly involved in forced expiration, and the diaphragm contracts and moves downward during inspiration but does not elevate the rib - cage.

Answer:

B. External intercostal