Final answer:
Diffusion is the movement of molecules from an area of high concentration to an area with a lower concentration, and it does not require added energy.
Step-by-step explanation:
Title: Movement of molecules
Diffusion is the movement of molecules from an area of high concentration to an area with a lower concentration. This movement occurs due to the random motion of molecules and does not require added energy.
Thus, the title that best fits Rahma's notes on the movement of molecules is B) Moves from high concentration to low concentration.