Given that $\text{'}\mathrm{A}\text{'} \mathrm{is} {\mathrm{SO}}_2 \mathrm{and} \text{'}\mathrm{B}\text{'} \mathrm{is} {\mathrm{SO}}_3;$ True statement about ‘A’ and ‘B’ is   (LA=Lewis acid  : LB=Lewis base)

 ${\mathrm{SO}}_2$ 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 ;

${\mathrm{SO}}_3$ 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;