Answer:
II. There is an electronegativity difference between the bonded atoms.
Explanation:
In a compound that has a number of individual dipoles(weaker force of attractions between compounds). There exist a weaker intermolecular force of attraction ( Vander waal's forces), these force of attraction arises from fluctuating dipoles in atom molecules brought by the movement of electrons around the atomic nucleus. They possess weak electronegativity difference between the bonded atoms because they have less energy to break these weaker bonds.
Also, individual dipoles can interact with each other in an way which will also increase the boiling point and as boiling point increases there is decrease in electronegativity difference between the bonded atoms.
On the other-hand, A polar compound are ionic compounds and the bonding between them are electrovalent bonding because of their high melting and boiling points. They possess high electronegativity.
