Compound X is an alcohol with only three carbon atoms. Compound Y is an alcohol with only four carbon atoms. Both compounds follow the general formula $\mathrm{C}_n\mathrm{H}_{2n+1}\mathrm{OH}$. Which row gives the numbers of structural isomers of compounds X and Y that are unbranched alcohols?
- AX: 1, Y: 2
- BX: 2, Y: 2
- CX: 2, Y: 3
- DX: 1, Y: 3