**Core Concept**
The Na+ K+ pump is an essential transport mechanism that maintains the resting membrane potential and ionic balance in cells, particularly in neurons and muscle fibers. It uses the energy from ATP hydrolysis to pump three sodium ions out of the cell and two potassium ions into the cell, against their concentration gradients.

**Why the Correct Answer is Right**
The Na+ K+ pump uses the enzyme Na+/K+-ATPase (also known as ATPase 3A2) to catalyze the hydrolysis of ATP and generate the energy needed to transport ions across the cell membrane. This enzyme is a transmembrane protein that spans the cell membrane, with the ATP-binding site on the cytoplasmic side and the ion-binding sites on the extracellular side.

**Why Each Wrong Option is Incorrect**
* **Option A:** This option is not provided.
* **Option B:** This option is not provided.
* **Option C:** This option is not provided.
* **Option D:** This option is not provided.

**Clinical Pearl / High-Yield Fact**
The Na+ K+ pump is an essential component of the sodium-potassium pump, which is used in the treatment of certain types of heart failure and hypertension. Digitalis glycosides, such as digoxin, inhibit the Na+ K+ pump, increasing the intracellular concentration of sodium ions and enhancing the contractility of the heart.

**Correct Answer:** D. Na+/K+-ATPase