Answer: it is an intermolecular force
Step-by-step explanation:
An intermolecular force is a force that holds molecules of a substance together in a particular state of matter. When a molecule is composed of different atoms having a large electro negativity difference, the bonding pair of electrons is attracted to nucleus of one of the bonding atoms more than it is to the nucleus of the less electronegative atom. A permanent dipole thus results in the molecule. This permanent dipole can attract the permanent dipole in another molecule of the same substance leading to strong dipole-dipole interaction.