Which of the following species contains three bond pairs and one lone pair around the central atom?

1. ${\text{PCl}}_3$: Phosphorus (Group 15) has 5 valence electrons. It uses 3 electrons to bond with 3 Cl atoms. Remaining 2 electrons form one lone pair. Total: 3 B.P. + 1 L.P.2. ${\text{H}}_2\text{O}$: Oxygen has 6 valence electrons. 2 B.P. + 2 L.P.3. ${\text{BF}}_3$: Boron has 3 valence electrons. 3 B.P. + 0 L.P.4. ${\text{NH}}_2^{-}$: Nitrogen has 5 valence electrons + 1 = 6. 2 B.P. + 2 L.P.