You are a database administrator for your company. The company uses a SQL Server 2005 database that includes a table named Inventory. The table contains a column named Price. A company policy states that the value in the Price column cannot be decreased by more than 10 percent in any single database operation. Updates to the Price column are made by various means， including by using ad hoc queries. You need to ensure that this company policy is enforced.
What should you do？（）

A.Create a trigger that rolls back changes to the Price column that violate company policy.
B.Create a stored procedure that disallows changes to the Price column that violate company policy.
C.On the Price column， create a check constraint that requires a specified minimum value.
D.On the Price column， create a foreign key constraint to a table that contains valid prices.