Incorrect statement  about oxoanions and oxoacids of 16th group is

${\mathrm{SO}}_3^{-2}$ion is Pyramidal

Hybridisation of Sulphur is  ${\mathrm{sp}}^3$   (Option (3) is correct)

No.of bond pairs = Attached atoms to central atom = 3

No.of lonepairs = Electronpairs - Bond pairs = 4-3 =1

Thus the central atom 'S' in Sulphite ion has

3 bond pairs + 1 lone pair around it

According to VSEPR theory

A bond pair can be single bond pair (or) double bond pair (or) triple bond pair

Oxidation state of 'S' in ${\mathrm{SO}}_3^{-2}$ = +4

Total bonds =4

Attached atoms = $\mathrm{\sigma }$ bonds = 3 ;

$\mathrm{\pi } \mathrm{bonds}=4-3=1 ;$

The structure of ${\mathrm{SO}}_3^{-2}$ will be

structure of  ${\mathrm{SO}}_4^{-2}$ will be

Both are stabilised through resonance

option(2) ---  Down the group acidic strength of oxides & oxyacids decreases