$HCl{O}_4$  is a stronger acid than  $HClO.$  The correct statement is

In  $HCl{O}_4$ hydrogen is attached to  $Cl$ while in  $HClO.$ It is attached to oxygen

 $Cl{O}_4^{-}$ ion is more stabilized than  $Cl{O}^{-}$

$HCl{O}_4$  is less solvated in water than  $HClO$

$Cl{O}_4^{-}$  ion has lower hydration energy than  $Cl{O}_{ }^{-}$