The correct option is B SO2
Steric Number (x) = 12(V+M − C+A).
where, M = number of monovalent surrounding atoms
V = number of valence electrons on the central atom
C = charge (with sign)
A=charge on anion
H=12(V+M−C+A)
(i) CO2:H=12(4+0−0+0)=2
∴ sp hybridisation.
(ii) SO2:H=12(6+0−0+0)=3
∴ sp2 hybridisation.
(iii) XeF4:H=12(8+4−0+0)=6
∴ sp3d2 hybridisation.
(iv) CO:H=12(4+0−0+0)=2
∴ sp hybridisation.