Rain falls from the sky. The sky is clear of clouds. Water droplets appear on the grass. Water droplets disappear from the grass.
A student is investigating the temperature at which evaporation takes place. Which statement best shows that evaporation has taken place?

Options:
- Rain falls from the sky.
- The sky is clear of clouds.
- Water droplets appear on the grass.
- Water droplets disappear from the grass.

Water droplets disappear from the grass.