Assertion (A): $S{O}_3$ has planar structure

Reason (R): S atom in $S{O}_3$ is $s{p}^2$ hybridized and $O-S-O$ bond angle is ${120}^0$

Both A and R are true and R is correct explanation A

Both A and R are true and R is not explaining A

A is true, R is false

A is false, R is true