Concept:2-methylpropan-2-ol is an alcohol where the carbon bearing the −OH group is bonded to three other carbon atoms, making it a tertiary alkanol.Explanation:The structure of 2-methylpropan-2-ol is (CH3)3COH. The carbon attached to the hydroxyl group is bonded to three methyl groups, with no hydrogen atom on that carbon. In alcohols, the degree is determined by the number of alkyl groups attached to the hydroxyl-bearing carbon. Since three alkyl groups are attached, it is a tertiary alkanol.Answer:C. tertiary alkanol