Which of the following does NOT give a yellow precipitate in the iodoform test?

Ethanol, ethanal and propan-2-ol all contain $\mathrm{CH}{}_3\mathrm{CH}(\mathrm{OH}){}^{-}$ or $\mathrm{CH}{}_3\mathrm{CO}{}^{-}$ (after oxidation). Methanol has neither a methyl group on a carbinol carbon nor a methyl ketone unit, so it gives no iodoform.