Extraction of zinc from zinc blende $(ZnS)$ is achieved by:

Roasting is generally done in case of the following:

In order to bring initial chemical change in the ore,the process of heating of ore below its melting point is known as

The role of calcination in metallurgical operations is

Given below are two statements:
Statement-$I$ : In the metallurgy process,sulphide ore is converted to oxide before reduction.
Statement-$II$ : Oxide ores in general are easier to reduce.
In the light of the above statements,choose the most appropriate answer from the options given below :

Which of the following statements,about the advantage of roasting of sulphide ore before reduction,is not true?