In this context, "Your State of Domicile" refers to your state of domicile at the "present", which for the 2016 tax year is 12/31/2016. That would be SC.
The question would be better stated as "Where were you domiciled (on 12/31/2016)?"
If you answered the Personal Interview questions correctly, the CA state tax interview will ask the right questions to determine when you stopped being a resident of CA.