In melting of iron, which of the following reactions takes place in Bladt Furnace at 400°C- 600°C________?
A. CaO+ SiO2——> CaSiO3
B. 2FeS+3O2——–> 2Fe+ SO2
C. FeSiO3———> FeSiO3
D. Fe2O3+ 3CO——–> 2Fe+ 3CO2