## **Core Concept**
Oxygen therapy is a medical treatment that provides a patient with extra oxygen. It is used to treat various conditions, including respiratory and cardiac diseases. However, like any medical treatment, oxygen therapy can have side effects.

## **Why the Correct Answer is Right**
The correct answer, , is related to the fact that oxygen therapy can cause several side effects, including absorption atelectasis, oxygen toxicity, and decreased cardiac output. However, one option does not belong to the common side effects of oxygen therapy.

## **Why Each Wrong Option is Incorrect**
* **Option A:** - This option is incorrect because is indeed a side effect of oxygen therapy. Prolonged exposure to high concentrations of oxygen can lead to the formation of free radicals, causing damage to lung tissue.
* **Option B:** - This option is incorrect because is a known side effect of oxygen therapy. High concentrations of oxygen can cause vasoconstriction, leading to decreased cardiac output.
* **Option D:** - This option is incorrect because is also a side effect of oxygen therapy. Dry oxygen can irritate the mucous membranes, leading to in the eyes.

## **Clinical Pearl / High-Yield Fact**
A key point to remember is that while oxygen therapy is life-saving, it should be used judiciously, and the concentration and duration of therapy should be carefully monitored to minimize side effects. A classic clinical correlation is that patients with chronic obstructive pulmonary disease (COPD) may require lower concentrations of oxygen to avoid suppressing their hypoxic drive to breathe.

## **Correct Answer:** .