The sodium-potassium pump is an example of passive transport. active transport. isotonic transport. endocytosis transport.

The sodium-potassium is an example of  Active transport. 
Cells often need to create concentration gradients across membranes. The concentration of a molecule is much higher on one side of the membrane than the other when a concentration gradient exists. Sodium potassium pump is vital to numerous bodily processes, such as nerve cell signalling, heart contractions, and kidney functions. Active transport involves movement of substances against a concentration gradient.