Given that 'A' is SO2 and 'B' is SO3; True statement about ‘A’ and ‘B’ is   (LA=Lewis acid  : LB=Lewis base)

SO2 contains a lone pair on central atom it can act like Lewis base;It has multiple bonds between dissimilar atoms hence it acts like a Lewis acid ;SO3 contains multiple bonds between dissimilar atoms hence it acts like Lewis acid;It has no lonepair on central atom. It cannot act like Lewis base;