Which of the following does NOT turn orange chromic acid ($\mathrm{CrO}{}_3$ in aqueous $\mathrm{H}{}_2\mathrm{SO}{}_4$) green within a few seconds?

Primary and secondary alcohols are oxidised by chromic acid, reducing $\mathrm{Cr}(\mathrm{VI})$ (orange) to $\mathrm{Cr}(\mathrm{III})$ (green). A tertiary alcohol has no hydrogen on the carbinol carbon and is not oxidised under these conditions.