In context with the industrial preparation of hydrogen from water gas `(CO+H_(2))` , which of the following is the correct statement ?
A. CO and `H_(2)` are fractionally separated using differences in their densities
B. CO is removed by absorption in aqueous `Cu_(2)Cl_(2)` solution
C. `H_(2)` is removed through occulsion with Pd
D. CO is oxidised to `CO_(2)` with steam in the presence of a catalyst followed by absorption of `CO_(2)` in alkali
