A patient has a diagnosis of Impaired Gas Exchange. Which assessment finding shows that the interventions have been effective?

A. The patient appears comfortable: Comfort alone does not indicate that gas exchange has improved. A patient may feel better subjectively while still having inadequate oxygenation or carbon dioxide retention. B. The patient is coughing up copious white sputum: While expectoration can help clear airways, copious sputum does not directly indicate effective gas exchange. Excessive secretions may still compromise oxygenation if not adequately managed. C. The patient's Spo2 is 97% on 2L NC: An oxygen saturation of 97% demonstrates that the patient is effectively oxygenating at a low-flow supplemental oxygen level. This objective measure indicates that interventions targeting gas exchange, such as oxygen therapy and airway management, are effective. D. The patient is able to move out of bed without difficulty: Mobility indicates functional improvement but does not directly reflect gas exchange status. A patient may move without apparent difficulty yet still have hypoxemia or impaired oxygen delivery.