The statement in the question is FALSE, which corresponds to Option B. In the van der Waal's equation, $$ (P + \frac{n^2 a}{V^2})(V - nb) = nRT $$, the constants 'a' and 'b' have specific roles, but they do not represent the actual volume of the gas molecules directly.

The constant 'a' in the van der Waals equation accounts for the intermolecular forces of attraction between the gas molecules. A higher value of 'a' indicates stronger attraction between the molecules, which affects how closely they can be packed together. The term $$ \frac{n^2 a}{V^2} $$ adds to the pressure 'P' to compensate for the lowering of pressure due to these attractive forces.

On the other hand, the constant 'b' represents the volume occupied by the gas molecules themselves, known as the excluded volume. It corrects the volume term 'V' in the ideal gas equation $$ PV = nRT $$, modifying it to $$ (V - nb) $$ to account for the volume that cannot be occupied by other molecules because it is already taken up by the gas molecules themselves.

Therefore, it is 'b', not 'a', that reflects the actual volume of the gas molecules in the van der Waal's equation.