The gas that can be dried using concentrated tetraoxosulphate(VI) acid (H2SO4) must not react with it. Concentrated H2SO4 is a strong acid, an oxidizing agent, and

The gas that can be dried using concentrated tetraoxosulphate(VI) acid ($\text{H}_2\text{SO}_4$) must not react with it. Concentrated $\text{H}_2\text{SO}_4$ is a strong acid, an oxidizing agent, and a dehydrating agent.

Let's examine each option:

• A) Hydrogen bromide ($\text{HBr}$): $\text{HBr}$ is a reducing agent. Concentrated $\text{H}_2\text{SO}_4$ will oxidize $\text{HBr}$ to bromine ($\text{Br}_2$).

  $$\text{2HBr} + \text{H}_2\text{SO}_4 \rightarrow \text{Br}_2 + \text{SO}_2 + \text{2H}_2\text{O}$$

  Therefore, $\text{HBr}$ cannot be dried by concentrated $\text{H}_2\text{SO}_4$.

• B) Sulphur(IV) oxide ($\text{SO}_2$): $\text{SO}_2$ is an acidic gas. It does not react with concentrated $\text{H}_2\text{SO}_4$ because both are acidic. Therefore, $\text{SO}_2$ can be dried by concentrated $\text{H}_2\text{SO}_4$.

• C) Hydrogen sulphide ($\text{H}_2\text{S}$): $\text{H}_2\text{S}$ is a strong reducing agent. Concentrated $\text{H}_2\text{SO}_4$ will oxidize $\text{H}_2\text{S}$ to sulfur ($\text{S}$).

  $$\text{H}_2\text{S} + \text{H}_2\text{SO}_4 \rightarrow \text{S} + \text{SO}_2 + \text{2H}_2\text{O}$$

  Therefore, $\text{H}_2\text{S}$ cannot be dried by concentrated $\text{H}_2\text{SO}_4$.

• D) Ammonia ($\text{NH}_3$): $\text{NH}_3$ is a basic gas. It will react with the acidic concentrated $\text{H}_2\text{SO}_4$ to form ammonium sulfate.

  $$\text{2NH}_3 + \text{H}_2\text{SO}_4 \rightarrow (\text{NH}_4)_2\text{SO}_4$$

  Therefore, $\text{NH}_3$ cannot be dried by concentrated $\text{H}_2\text{SO}_4$.

Based on this analysis, only sulphur(IV) oxide can be dried using concentrated tetraoxosulphate(VI) acid.

The final answer is $\boxed{\text{B}}$.