单项选择题 You are creating a Windows application for a financial services provider by using the .NET Framework 3.5. You write the following code segment in the form （Line numbers are included for reference only.） The connection string for the financial services database is stored in the variable named connString.You need to ensure that the form populates a DataGridView control named gridCAT.   Which code segment should you add at line 03？（）

单项选择题 You are creating a Windows Forms application for inventory management by using the .NET Framework 3.5.The application provides a form that allows users to maintain stock balances. The form has the following features：  （1）A dataset named dsStockBalance to store the stock information  （2）A business component named scInventory.   The scInventory component provides a method named Save. You need to ensure that only the modified stock balances of dsStockBalance are passed to the scInventory Save method.   Which code segment should you use？（）

单项选择题 You are creating a Windows Forms application by using the .NET Framework 3.5.You need to populate a list box control along with category names by using a DataReader control. Which code segment should you use？（）