The correct option is B CO2−3NO−3,SO3
The group having triangular planar structures is CO2−3NO−3,SO3
In CO2−3 ion, C atom is sp2 hybridised. This results in triangular planar structure.
In NO−3 ion, N atom is sp2 hybridised. This results in triangular planar structure.
In SO3, S atom is sp2 hybridised. This results in triangular planar structure.
In all the above molecules/ions, the central atom has 3 binding domains and a bond angle of 120∘.
Note:
NCl3,NF3andNH3 are pyramidal.
BCl3andBF3 have triangular planar structure.