The correct option is C Humidity
Evaporation is a process where liquid converts to gases. It is a surface phenomenon.
The factors affecting evaporation are:
∙ Surface area - The increase in surface area increases the rate of evapoartion as it is a surface phenomena.
∙ Temperature - The movement of the particles increases which helps them to escape from the surface easier and faster.
∙ Humidity - If the humidity (water vapour) in the air is more, it is difficult for the other water particles from any surface to enter into the atmosphere. Thus, it decreases the rate of evaporation.
The density of the substance has no role in the process of evaporation.