The electronegativity difference between N and F is greater than that between N and H yet the dipole moment of ${\text{NH}}_3$ ($1.5\text{D}$) is larger than that of ${\text{NF}}_3$ ($0.2\text{D}$). This is because :

1. A
   in ${\text{NH}}_3$ as well as in ${\text{NF}}_3$ the atomic dipole and bond dipole are in the same direction
2. B
   in ${\text{NH}}_3$ the atomic dipole and bond dipole are in the same direction whereas in ${\text{NF}}_3$ these are in opposite directions
3. C
   in ${\text{NH}}_3$ as well as in ${\text{NF}}_3$ the atomic dipole and bond dipole are in opposite directions
4. D
   in ${\text{NH}}_3$ the atomic dipole and bond dipole is in the opposite directions whereas in ${\text{NF}}_3$ these are in the same directions