Explanation:
The oxidation state of an element is a measure of the number of electrons that an atom has gained or lost in order to form a chemical bond with another atom. In the case of sulfur (S), the maximum oxidation state it can have is +6.

Peroxy group:
The peroxy group is a functional group consisting of a single oxygen atom bonded to another oxygen atom by a single bond (-O-O-). In compounds containing the peroxy group, the oxidation state of oxygen is -1. Therefore, in compounds such as H2S2O8 (peroxydisulfuric acid), where there are two peroxy groups, the total oxidation state of the oxygen atoms is -4. Since the overall charge of the compound is 0, the oxidation state of sulfur must be +6 in order to balance out the negative oxidation states of the oxygen atoms.

Superoxo group:
The superoxo group is a functional group consisting of a single oxygen atom bonded to the central atom by a double bond (-O2-). In compounds containing the superoxo group, the oxidation state of oxygen is -1/2. Therefore, in compounds such as H2SO5 (peroxymonosulfuric acid), where there is one superoxo group, the total oxidation state of the oxygen atom is -1/2. Since the overall charge of the compound is 0, the oxidation state of sulfur must be +6 in order to balance out the negative oxidation state of the oxygen atom.

Neutral O2:
Neutral O2 refers to molecular oxygen, which does not have any charge. Since there is no charge, the oxidation state of oxygen in O2 is 0. Therefore, compounds containing only neutral O2 do not contribute to the oxidation state of sulfur.

Ozone:
Ozone (O3) is a molecule consisting of three oxygen atoms bonded together. In ozone, the oxidation state of oxygen is 0. Therefore, compounds containing ozone do not contribute to the oxidation state of sulfur.

Therefore, the correct answer is option 'A' - the presence of peroxy groups in compounds such as H2S2O8 and H2SO5 leads to a +6 oxidation state of sulfur.