[Steenrod]

Here is a question from my book:

Phenol is treated with Zn dust to form A.A is treated with [itex] H_2SO_4[/itex] in presence of [itex]SO_3[/itex] to obtain B. Identify A and B.

Here is what I did: Phenol is reduced by zinc dust to benzene(A). Benzene when treated with [itex] H_2SO_4[/itex] in presence of [itex]SO_3[/itex] gives [itex]C_6H_5SO_3H[/itex].I have guessed B and I cannot really explain it.Can anyone comment if I correct and why ?

[discodermolide]

It is just a normal sulfonation of an aromatic ring.