Water kept in an earthen pot becomes cool during summer due to:
Evaporation
The explanation for the correct option:
Evaporation is the process in which a liquid changes to a vapor state at all temperatures.
Option (A): During evaporation, some liquid particles leave the surface of the liquid by gaining kinetic energy and get converted into vapours.
Thus, the average kinetic energy of the remaining particles in the liquid decreases, and the temperature falls.
So, when a liquid evaporates, it makes the surface cool from where evaporation takes place.
The explanation for the incorrect options:
Option (B): Diffusion is the process of movement of molecules under a concentration gradient.
Option (C): Vaporization can be defined as the process in which the liquid state changes into the vapour state.
Option (D): Transpiration is an essential process of eliminating the excess amount of water from the plant's aerial parts.
Hence, option (A) is the correct option.