Answer:
Hydrogen bonding
Step-by-step explanation:
The molecule of benzophenone (in the picture below) is polar because it has a bond of carbon and oxygen and these elements have huge differences of electronegativity, so they'll have partial charges: oxygen will be with negative partial charge because it has higher electronegativity (it attracts the electrons better).
The molecule of hexane (in the picture below) only has bonds between carbon and hydrogen which have close electronegativity, so the molecule is nonpolar. But, it can form an induced dipole, and the hydrogen will have a partial positive charge for a moment.
When these two molecules approach, the hydrogen and the oxygen must form a bond, which is called hydrogen bonding, and always occurs between hydrogen and an atom with high electronegativity (N, O, and F).