What is known as Thomas slag?

Which of the following is correctly matched?

The correct statement$(s)$ related to processes involved in the extraction of metals is(are):
$(A)$ Roasting of Malachite produces Cuprite.
$(B)$ Calcination of Calamine produces Zincite.
$(C)$ Copper pyrites is heated with silica in a reverberatory furnace to remove iron.
$(D)$ Impure silver is treated with aqueous $KCN$ in the presence of oxygen followed by reduction with zinc metal.

Copper matte is composed of . . . . . .

The $INCORRECT$ statement is:

For the following statements,mark $T$ for true and $F$ for false statement.
Statement $1$: $SnO_2 +$ wolframite,in this $SnO_2$ is magnetic while wolframite is non-magnetic in nature.
Statement $2$: Argentite ore is concentrated by froth floatation method.
Statement $3$: Copper and lead ores are reduced by self-reduction method.
Statement $4$: In metallurgy of $Fe$,$CO$ is used as a reducing agent at low temperature.