In the given question, the movement of gases across the cell is accomplished by the process of diffusion.
• The movement of molecules from a region of higher concentration to a region of lesser concentration is known as diffusion.
• The movement of gases like carbon dioxide and oxygen across a cell membrane takes place by the process of simple diffusion.
• In the process, no energy is used and is mediated by the differences in concentration on either side of the cell membrane.
• In simple organisms, like protozoa and bacteria, the exchange of gases across their membranes takes place by the process of diffusion.
Thus, correct answer is option 2, that is, diffusion.
To know more about:
https://brainly.com/question/1395899