The answer is surname. In 1957, Article 809 of the Korean Civil Code made it illegal to marry someone with the same surname or ancestral home. On 16 July 1997, the Constitutional Court of Korea ruled the article unconstitutional.
It would be primarily "D. executive power" that gives a state the authority to protect the health and safety of the state’s citizens, since these powers can be acted upon without express approval of a legislature or court.
States being able to issue their own paper money would lead to problems such as counterfeiting and people not being able to use money from a certain state in a different state.
