The correct option is C 2Fe2O3
Calcination is a process in which the ore is heated strongly in the absence of air to remove volatile impurities. It involves the thermal decomposition of the ores. When the hydrated ferrous salt is calcinated it forms ferric oxide and water. The reaction takes place as follows:
2Fe2O3.3H2O(s)Calcination−−−−−−−→2Fe2O3(s)+3H2O(l)