Perfume sprayed from a bottle spreads more easily in a warm room of 25°C than in a cool room of 15°C. Which of the following correctly compares perfume molecules at 25°C to those at 15°C?

Available options:
I. At 25°C, they have more mass.
II. At 25°C, they are moving faster.
III. At 25°C, they have less kinetic energy.
IV. At 25°C, they are decreasing in volume.

