In which scenario can both metabolic and respiratory alkalosis occur?

Hypokalemia, which is a low level of potassium in the blood, can lead to both metabolic and respiratory alkalosis. When potassium levels are low, the kidneys conserve potassium by excreting hydrogen ions, leading to a decrease in acidity (metabolic alkalosis).

In addition, hypokalemia can stimulate hyperventilation due to increased respiratory drive, which can further lead to respiratory alkalosis as the increased breathing rate decreases carbon dioxide levels in the blood. The combination of these mechanisms results in a situation where both metabolic and respiratory alkalosis can be present simultaneously.

In contrast, the other options—hyperchloremia, hypernatremia, and hyperphosphatemia—do not directly contribute to the dual development of metabolic and respiratory alkalosis in the same way that hypokalemia does. Each of those conditions may affect acid-base balance, but they do not typically result in the coexistence of both forms of alkalosis.