Diffusion is the movement of molecules from a. an area of low concentration to an area of high concentration.
b. an area of high concentration to an area of low concentration.
с. an area of equilibrium to an area of high concentration.
d all of the above

An area of high concentration to an area of low concentration.

Explanation:

Diffusion is the dispersion of a substance in an area of high concentration to an area of low concentration. Diffusions occur in liquids and gases.

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1. is geographic distribution

2 is increasing complexity

3 is transitional forms