Answer is: C) high melting point and high boiling point.
Intermolecular forces are the forces between molecules.
The stronger are intermolecular forces, the higher is boiling point of compound, because more energy is needed to break interaction between molecules.
There are several types of intermolecular forces: hydrogen bonding, ion-induced dipole forces, ion-dipole forces andvan der Waals forces.
For example, water has high boiling and melting points because strong hydrogen bonds between water molecules (intermolecular force). It is because oxygen has largest electronegativity and smallest atomic radius of all elements in group.
