The compound obtained on reaction of iron with steam is/are :
(a) ${\mathrm{Fe}}_2{\mathrm{O}}_3$
(b) ${\mathrm{Fe}}_3{\mathrm{O}}_4$
(c) $\mathrm{FeO}$
(d) ${\mathrm{Fe}}_2{\mathrm{O}}_3$ and ${\mathrm{Fe}}_3{\mathrm{O}}_4$
OR
An element ' $\mathit{X}$ ' reacts with ${\mathrm{O}}_2$ to give a compound with a high melting point. This compound is also soluble in water. The element ' $\mathrm{X}$ ' is likely to be :
(a) iron
(b) calcium
(c) carbon
(d) silicon