You need to ensure that the Cust_CalcData column is implemented appropriately. What should you do?（）

• A、Specify that the Cust_CalcData column must be implemented as a computed column of the table. 
• B、Specify that the Cust_CalcData column must be indexed using a non-clustered index.
• C、Specify that the Cust_CalcData column must be implemented as a column that uses a user-defined data type.
• D、Specify that the Cust_CalcData column must be updated by a SQL Server Agent job that runs nightly.