You are creating a Windows Forms application by using the .NET Framework 3.5. You plan to modify a list of orders within a DataGridView control in the application. You need to ensure that a value is required in the first column of the grid control. <br /> Which code segment should you use?()<br /> <img src="https://nimg.ppkao.com/2018-08/zhoulian/2018080109415432325.jpg?sign=58eb34ad054c66e88fdf0a8d28ce2cfb&t=62d2ec25" />
A、A
B、B
C、C
D、D