Which of the following statements are correct for alkali metal compounds?
$(i)$ Superoxides are paramagnetic in nature.
$(ii)$ The basic strengths of hydroxides increase down the group.
$(iii)$ The conductivity of chlorides in their aqueous solutions decreases down the group.
$(iv)$ The basic nature of carbonates in aqueous solutions is due to cationic hydrolysis.

• A
  $(i)$,$(ii)$ and $(iii)$ only
• B
  $(i)$ and $(ii)$ only
• C
  $(ii)$,$(iii)$ and $(iv)$ only
• D
  $(iii)$ and $(iv)$ only