Which of the following orders of relative strength of acid is correct?

What is a protonic acid?

Which of the following is not a $Br\o nsted$ acid?

Review the equilibrium and choose the correct statement:
$HClO_4 + H_2O \rightleftharpoons H_3O^{+} + ClO_4^-$

Which of the following is a conjugate acid-base pair?

The dissociation constant values of three acids $A$,$B$ and $C$ are $1.8 \times 10^{-5}$,$1.5 \times 10^{-4}$ and $5.2 \times 10^{-8}$ respectively. The correct order of increasing basic nature of their conjugate bases is $-$