The respiratory structure that contracts and relaxes to allow air to flow in and out of the lungs is option(c) i.e, the diaphragm.
<h3>What is
the diaphragm?</h3>
The diaphragm, a delicate skeletal muscle that separates the chest from the belly, is located at the base of the chest. When you breathe in, it flattens and shrinks. As a result, the lungs experience a vacuum effect that draws air in. The diaphragm relaxes and the air is forced out of the lungs when you exhale.
signs of diaphragm issues:
- Acid reflux, heartburn, coughing, and difficulty swallowing.
- alterations to skin tone (skin may turn blue).
- rapid heartbeat, pressure in the chest, and/or breathing difficulties (especially when lying down).
- Headaches.
- Hiccups that persist or recur frequently.
Patients who need surgery for conditions affecting the chest, including diaphragm issues, are treated by a thoracic surgeon.
To know more about diaphragm refer to: brainly.com/question/12822939
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