The correct answer is: Calcination.
Calcination is a process of heating a material to a high temperature, below its melting point, in the absence of air. This process is used to remove water or other volatile compounds from the material. Calcination is often used to prepare ores for further processing, such as smelting.
Refining is a process of purifying a metal by removing impurities.
This process can be done by a variety of methods, including electrolysis, distillation, and chemical treatment.Roasting is a process of heating a material to a high temperature in the presence of air. This process is used to convert a material into a different form, such as a metal oxide. Roasting is often used to prepare ores for further processing, such as smelting.
Smelting is a process of extracting a metal from its ore by heating it to a high temperature and melting it. The molten metal is then poured into molds to form ingots.
In the case of heating of a ore below its melting point in the absence of air, the correct answer is calcination. This is because calcination is a process of heating a material to a high temperature, below its melting point, in the absence of air. This process is used to remove water or other volatile compounds from the material. Calcination is often used to prepare ores for further processing, such as smelting.