In which equation does the iron undergo oxidation?
- A$\text{C} + \text{FeO} \rightarrow \text{CO} + \text{Fe}$
- B$3\text{CO} + \text{Fe}_2\text{O}_3 \rightarrow 3\text{CO}_2 + 2\text{Fe}$
- C$\text{Fe}_2\text{O}_3 + \text{H}_2 \rightarrow 2\text{FeO} + \text{H}_2\text{O}$
- D$\text{PbO} + \text{Fe} \rightarrow \text{Pb} + \text{FeO}$