The given formula, (CH3)3COH, represents an alkanol with a hydroxyl (-OH) group attached to a carbon atom. To determine whether it is a primary, secondary, or tertiary alkanol, we need to look at the carbon atom to which the -OH group is attached and count the number of carbon atoms that are directly bonded to it. In this case, the carbon atom to which the -OH group is attached is bonded to three other carbon atoms, which means that it is a tertiary carbon. Therefore, the alkanol is a tertiary alkanol. However, the question also gives an option for trihydric alkanol, which means an alkanol with three hydroxyl (-OH) groups attached to it. The given formula has only one hydroxyl group, so it cannot be a trihydric alkanol. Therefore, the correct answer is: tertiary alkanol.