Identify a common cause of hypoxia.

Pneumonia is a common cause of hypoxia because it directly affects the lungs, leading to impaired gas exchange. When the alveoli in the lungs become inflamed and filled with fluid or pus due to infection, their ability to transfer oxygen into the bloodstream and eliminate carbon dioxide is significantly reduced. As a result, the oxygen saturation in the blood drops, leading to a state of hypoxia, where the body or specific tissues do not receive enough oxygen for proper functioning.

In contrast, conditions like a heart attack primarily involve the heart and its ability to pump blood efficiently, which can eventually lead to decreased oxygen delivery but are not as direct in affecting the oxygenation of blood as pneumonia is. Dehydration can cause other health issues, but it is not a direct cause of hypoxia; rather, it affects other bodily systems. Hyperventilation may lead to increased oxygen levels in the blood temporarily, often causing respiratory alkalosis rather than hypoxia.