The ease of adsorption of the hydrated alkali metal ions on ion-exchange resins follows the order:
A. `Li^(+) lt K^(+) lt Na^(+) lt Rb^(+)`
B. `Rb^(+) lt K^(+) lt Na^(+) lt Li^(+)`
C. `K^(+) lt Na^(+) lt Rb^(+) lt Li^(+)`
D. `Na^(+) lt Li^(+) lt K^(+) lt Rb^+)`