Question
Match the column A with column B and select the correct code.
| Column A | Column B |
| 1. $- SO _3 H$ | (a) Prefix sulpho |
| 2. Mixed ether | (b) Chain isomerism |
| 3. All $2^{\circ}$ carbon | (c) $CH _3- O - C _2 H _5$ |
| 4. n -butane and isobutane | (d) Benzene |
