In which of the following sets of molecules,do the central atoms have the same hybridisation?

$A + 2Cl^{-} \rightarrow B$
Where $A$ is $PCl_4^+$ and $B$ is $PCl_6^-$.
Which of the following statements is $INCORRECT$:
$(I)$ From $B$ to $A$,the number of $d$-orbitals involved in hybridization increases.
$(II)$ From $A$ to $B$,the percentage of $p$-character in the $P-Cl$ bond increases.
$(III)$ The number of covalent bonds in $A$ and $B$ are the same.
$(IV)$ $B$ is a product of Lewis acid-base interaction,which is associated with super-octet molecules only.

The hybridisation of $N$ in $NO_2^{+}$,$NO_3^{-}$ and $NH_4^{+}$ respectively is

The hybrid state of sulphur in $SO_3$ molecule is

Consider the following reactions:
$(i)$ $PCl_3 + 3H_2O \to H_3PO_3 + 3HCl$
$(ii)$ $SF_4 + 3H_2O \to H_2SO_3 + 4HF$
$(iii)$ $BCl_3 + 3H_2O \to H_3BO_3 + 3HCl$
$(iv)$ $XeF_6 + 3H_2O \to XeO_3 + 6HF$
Then according to given information the incorrect statement is

Which of the following is true for carbon suboxide $(C_3O_2)$?