A table named Profits stores the total profit made each year within a territory. The Profits table has
columns named Territory, Year, and Profit.
You need to create a report that displays the profits made by each territory for each year and its
previous year.
Which Transact-SQL query should you use?

A.
SELECT Territory, Year, Profit,
LEAD(Profit, 1, 0) OVER (PARTITION BY Territory ORDER BY Year) AS PrevProfit
FROM Profits

B.
SELECT Territory, Year, Profit,
LAG(Profit, 1, 0) OVER (PARTITION BY Year ORDER BY Territory) AS PrevProfit
FROM Profits

C.
SELECT Territory, Year, Profit,
LAG(Profit, 1, 0) OVER (PARTITION BY Territory ORDER BY Year) AS PrevProfit
FROM Profits

D.
SELECT Territory, Year, Profit,
LEAD(Profit, 1, 0) OVER (PARTITION BY Year ORDER BY Territory) AS PrevProfit
FROM Profits

Explanation:
http://msdn.microsoft.com/en-us/library/hh231256.aspx
http://msdn.microsoft.com/en-us/library/hh213125.aspx