问题：

[单选]

You are responsible for maintaining a SQL Server 2005 database. Business analysts in the company routinely use a view named v CustomerSales to join the Customers and Sales tables in the database. They use the view to aggregate total sales by customer by month. You need to increase the performance of the view.
What should you do？（）

A . Update the view to use an outer join between the Customers and Sales tables.
B . Create a clustered index on the v CustomerSales view.
C . Create two separate views that do not contain any joinsone view named Customers for the Customers table and another one named v Sales for the Sales table.
D . Create a stored procedure for the business analysts that uses the v CustomerSales view.