Elements D and E both belong to Period 3. Within Period 3, element D has the smallest atomic radius. In Period 3, only two elements have a melting point lower than that of element E. Elements D and E combine to produce compound L. Which compound could be L?
- A$\text{MgCl}_2$
- B$\text{MgS}$
- C$\text{Na}_2\text{S}$
- D$\text{PCl}_3$