The correct option is D None of the above
α= Fraction of moles of the reactant that undergoes dissociation to form the products.
α can be any value from 0 to 1.
0 indicates no dissociation and 1 indicates complete dissociation.
Since degree of dissociation is the ratio of number of moles dissociated to the original moles i.e. molmol ratio. Hence, it is unitless.
Eg: if α=12, it means 50 % dissociation. Hence, α can be any fractional value between 0 to 1.