Question

the movement of ions through this membrane protein is an example of active transport. exocytosis. facilitated diffusion. osmosis.

Explanation:

Active transport moves substances against a concentration gradient using energy. Exocytosis is the process of cells releasing substances out of the cell. Osmosis is the diffusion of water across a semi - permeable membrane. Facilitated diffusion is the movement of substances (like ions) across a membrane with the help of membrane proteins down their concentration gradient without using energy. Since the question mentions movement of ions through a membrane protein without indicating energy use for moving against a gradient, it is facilitated diffusion.

Answer:

C. facilitated diffusion