Of the compounds, which one has the greatest relative formula mass, $M_r$? [$A_r$: $\text{K}$, $39$; $\text{N}$, $14$; $\text{O}$, $16$; $\text{Ca}$, $40$; $\text{C}$, $12$; $\text{Li}$, $7$; $\text{S}$, $32$; $\text{Mg}$, $24$; $\text{Cl}$, $35.5$]
- Acalcium carbonate
- Blithium sulfate
- Cmagnesium chloride
- Dpotassium nitrate