Identify the final product [D] obtained in the following sequence of reactions,

H? S? O? , peroxodisulphuric acid (Two S-OH, Four S = O, One S – O – O – S )

H? SO? , sulphurous acid (Two S-OH, One S = O bond)

H? S? O? , pyrosulphuric acid (Two S-OH, Four S=O, One S-O-S bond)

H? SO? , sulphuric acid (Two S – OH, Two S = O )

Kindly consider the following figure

Consider the image below