For real gases van der Waals' equation is written as (p+an2V2)(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: