The movement of atoms, ions, or molecules from a region of higher concentration to regions of lower concentration is called the movement of atoms, ions, or molecules from a region of higher concentration to regions of lower concentration is called active transport crenation diffusion spontaneous combustion

The answer to this question would be diffusion.

When a membrane is permeable to a certain atom, the atoms will be constantly moved from and into the membrane. The area with the higher concentration of atoms will move in higher speed, resulting that area is losing more atoms than the lower concentration. This process is called diffusion. Active transport happens when you move an atom from lower concentration into higher concentration.

The answer should be c.