Answer:
D
Step-by-step explanation:
Lithium has one valence electron, so it has one to give away to have an outer shell of 8.
Sulfur has 6 valence electrons, so it needs 2 to get an outer shell of 8.
If we have two Li, that means sulfur will get 2 e- and Li will give away 2 e-, so the formula is Li₂S.