Answer the following question given this paragraph: 

Osmosis is the special case of the diffusion of water. It's an important means of transport in cells because the fluid inside and outside cells is mostly water. Water can pass through the cell membrane by simple diffusion, but it can happen more quickly with the help of channel proteins. Water moves in or out of a cell by osmosis until its concentration is the same on both sides of the cell membrane.


Q: What is the diffusion of water known as?

 Choices:

- evaporation

- electrolysis

- hemostasis

- osmosis

A:
osmosis
