Which of the following ores is subjected to roasting during metallurgical operations for getting the metal oxide?

Heating of ore in the presence of air to remove sulphur impurities is called:

Which of the following sulphides,when heated strongly in air,gives the corresponding metal?

$A$ sulphide ore is first converted into its oxide before reduction. This is done because

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 :

In metallurgy,calcination is used for .........