This week's book giveaway is in the OCAJP 8 forum. We're giving away four copies of OCA Java SE 8 Programmer I Study Guide and have Edward Finegan & Robert Liguori on-line! See this thread for details.
I'll give you a hint: the question doesn't make any sense. Thread safety is not a property of an "attribute scope" (a nonsense term in itself.) Thread safety is a property of a class or of a pattern of data access.