For real gases van der Waals equation is written as
$\bigg( p + \frac{an^2}{V^2} \bigg) (V - nb) = nRT$
Where 'a' and 'b' are van der Waals constants .
Two sets of gases are :
(I)${ O2, CO2, H2}$ and $He$ (II) ${CH4, O2}$ and ${H2}$
The gases given in set-I in increasing order of 'b' and gases given in set-II in decreasing order of 'a', are arranged below. Select the correct order from the following :