The changing of gas into liquid on cooling, is called__________.
condensation
The explanation for the correct option:
Condensation: The process of converting the gaseous state into the liquid state on cooling.
The explanation for the incorrect options:
Vaporization: The process in which a liquid boils and changes to a gas is called vaporization.
Freezing: The process of liquid water changing to solid ice is termed freezing. The temperature at which it occurs is known as the freezing point.
Melting: The process in which solids change to a liquid is called melting. The melting point is the temperature at which solids change to a liquid.
Hence, The correct option is D.