Which of the following compounds has the highest dipole moment $(D)$?

Which of the following bonds is the most polar?

Which of the following exhibits a dipole moment?

Given below are two statements: one is labelled as Assertion $A$ and the other is labelled as Reason $R$.
Assertion $A$: $NH_3$ and $NF_3$ molecules have a pyramidal shape with a lone pair of electrons on the nitrogen atom. The resultant dipole moment of $NH_3$ is greater than that of $NF_3$.
Reason $R$: In $NH_3$,the orbital dipole due to the lone pair is in the same direction as the resultant dipole moment of the $N-H$ bonds. $F$ is the most electronegative element.

$H_2O$ is polar while $BeF_2$ is not. The reason for this is ...

Carbon tetrachloride has no net dipole moment because of