You have an XML schema collection named Sales.InvoiceSchema. You need to declare a variable
of the XML type named XML1. The solution must ensure that XML1 is validated by using
Sales.InvoiceSchema. Which code segment should you use? To answer, type the correct code in
the answer area.

Answer: See the explanation

Explanation:
DECLARE @XML1 XML(Sales.InvoiceSchema)

http://msdn.microsoft.com/en-us/library/ms176009.aspx