The three states of matter i.e. solid, liquid and gas exist due to :

1. Random motion of molecules in a substance
2. Intermolecular space
3. Intermolecular force of attraction
4. All of the above

All of the above

Reason — The three states of matter (solid, liquid, and gas) are determined by the random motion of molecules, the intermolecular space, and the intermolecular forces of attraction. In solids, molecules are tightly packed with strong forces and limited movement; in liquids, the molecules are less tightly packed, with weaker forces allowing them to move past each other; in gases, the molecules are far apart with very weak forces, allowing free movement.