You work as an application developer at Contoso.com. You use Microsoft .NET Framework 3.5 and Microsoft ADO.NET to develop an application. The Contoso.com network contains a Microsoft SQL Server 2005 server named DB01. Your application retrieve records from a  database named Trades that resides on DB01. The application connects to Trades by using an instance of the SqlConnection class with the following connection string.   "Data Source=DB01；UID=’mhamm’；PWD=’password’；"   When the application calls the Open method of the SqlConnection object， it displays the following： "Cannot open user default database. Login failed. Login failed for user ’mhamm’".  You need to make sure that you can connect to Trades when the user account for the connection is mhamm.   What should you do？ （）

• A、 Change the connection string as follows：Data Source=DB01；Initial Catalog=Trades；UID=mhamm； PWD=password；"
• B、 Create a login for Mia Hamm on DB01.
• C、 Create a database user object in Trades and map the object to the SQL Server 2005 Login of Mia Hamm.
• D、 Change the connection string as follows："Server=DB01；Database=Trades；UID=mhamm；PWD=password；"