Attractive forces between atoms/molecules become stronger as the particles move closer together. these attractive forces are called . options:
a) intermolecular
b) compounding
c) interstellar
d) elemental

Intermolecular

Explanation:

Intermolecular forces are the forces operating between the two molecules.  These forces are of short rang forces and also known as week intermolecular forces.

These forces only exist when molecules get close together by force of by cooling.

Example:

Hydrogen bond (intermolecular forces) exist in liquid water molecules but when we heat it the water molecule escape from surface by as hydrogen bond break by heating.

Compressed Natural Gas:

In this case the molecules of natural gas presses and the come closer so the distance between the molecules become less and force of attraction increase that attraction (intermolecular force ) is due to short distance.