Which of the following is obtained as a slag during the extraction of iron from iron oxide?

During the extraction of gold,the following reactions take place: $4Au + 8CN^{-} + 2H_2O + O_2 \longrightarrow 4[Au(CN)_2]^{-} + 4OH^{-}$ and $2[Au(CN)_2]^{-} + Zn \longrightarrow [Zn(CN)_4]^{2-} + 2Au$. $X$ and $Y$ are respectively:

Consider the following metallurgical processes:
$(i)$ Heating impure metal with $CO$ and distilling the resulting volatile carbonyl (boiling point $43\,^{\circ}C$) and finally decomposing at $150\,^{\circ}C$ to $200\,^{\circ}C$ to get the pure metal.
$(ii)$ Heating the sulphide ore in air until a part is converted to oxide and then further heating in the absence of air to let the oxide react with unchanged sulphide.
$(iii)$ Electrolysing the molten electrolyte containing approximately equal amounts of the metal chloride and $CaCl_2$ to obtain the metal.
The processes used for obtaining sodium,nickel and copper are,respectively,

The maximum temperature $1550$ $^oC$ is obtained in the ......... region of the blast furnace used in the extraction of iron.

Cryolite is

The slag consists of molten impurities generally in the form of