What type of alcohol?

[Grace_Stevenson_1A]

Why is number 20 a tertiary alcohol isn't it just attached to one carbon? (The carbon i outlined in purple) thank you!!!! :)))

[Mannat Sukhija 1E]

The classification of an alcohol is based on the classification of the carbon it is covalently bonded to. For example, the carbon you outlined in purple is a tertiary carbon because it forms 3 carbon-carbon bonds. Thus the alcohol group it is bonded to is a tertiary alcohol. An alcohol group can only be bonded to one carbon, so it is that carbon that gives the classification.