X is made up of a mixture containing two compounds of Group 2 elements. On heating, X undergoes thermal decomposition and yields a white solid together with only two gaseous products. One of those gases relights a glowing splint. What might the components of mixture X be?
- A$\text{MgCl}_2$ and $\text{CaCO}_3$
- B$\text{MgCO}_3$ and $\text{Ca(NO}_3)_2$
- C$\text{Mg(NO}_3)_2$ and $\text{Ca(NO}_3)_2$
- D$\text{MgO}$ and $\text{CaO}$