You need to implement a common table expression (CTE).
Which code segment should you use?
A.
 CREATE VIEW SalesByYear 
AS 
SELECT Year, 
Region, 
SUM(OrderTotal) 
FROM Orders 
GROUP BY Year, Region; 
GO 
SELECT Year, 
Region, 
Total 
FROM SalesByYear;
B.
 WITH SalesByYear(Year,Region,Total) 
AS (SELECT Year, 
Region, 
SUM(OrderTotal) 
FROM Orders 
GROUP BY Year,Region) 
SELECT Year, 
Region, 
Total 
FROM SalesByYear;
C.
 SELECT Year, 
Region, 
Total 
FROM (SELECT Year, 
Region, 
SUM(OrderTotal) AS Total 
FROM Orders 
GROUP BY Year, Region) AS [SalesByYear];
D.
 SELECT DISTINCT Year, 
Region, 
(SELECT SUM(OrderTotal) 
FROM Orders SalesByYear 
WHERE Orders.Year = SalesByYear.YEAR 
AND Orders.Region = SalesByYear.Region) AS [Total] 
FROM Orders;