The correct option is A 0
Entropy is a state function that is often erroneously referred to as the 'state of disorder' of a system. Qualitatively, entropy is simply a measure how much the energy of atoms and molecules become more spread out in a process and can be defined in terms of statistical probablities of a system or in terms of the other thermodynamic quantities.
2SO3(g)⟶2SO2(g)+O2(g) entropy increases because no of atoms increases.