Answer:
A. diffusion
Explanation:
Diffusion is a process in which molecules/ substances/ particles move from the region of their high concentration to the region of their low concentration. The moving particles may be of solid, liquid or gas. This can be understood by an example when the perfume bottle is open in one corner of a room, the fragrance is quickly spread in other corners of the room. This happens due to diffusion. Similarly, the open gasoline can fill the garage with the smell of gas due to diffusion.
