Hbr + h₂so₄ so₂ + br₂ + h₂o
what is the oxidation number of the oxidizing agent?
what is the oxidation number of the reducing agent?

The reaction equation is:
HBr + H₂SO₄ → SO₂ + Br₂ + H₂O

An oxidizing agent is a substance that itself becomes reduced and oxidizes the other chemical species in the reaction mixture. A reducing agent is similar, except that it becomes oxidized and reduces the other substance. 
In the reaction, the valency of bromine changes from -1 to 0, so it is oxidized, making it the reducing agent. The valency of sulfur changes from +6 to +4, so it is reduced, making it the oxidizing agent.

Option (b) is the correct answer.

Explanation:

Evaporation is defined as the process in which liquid state of a substance changes into vapor or gaseous state.

Condensation is a process in which vapors of a substance changes into liquid state upon cooling.

Transpiration is defined as the process in which water or moisture is absorbed by the roots of a plant. That is, a liquid is absorbed by a solid state.

Thus, we can conclude that states of matter which appear during the processes of evaporation, condensation, and transpiration are vapor, liquid, and solid.