End Sub

程序运行后，单击命令按钮，如果输入3，则在窗体上显示的内容是（　　　）

（A）3                    （B）4                 （C）5                        （D）6

5．       在窗体上画一个命令按钮，然后编写如下事件过程：

            Private Sub Command1_Click( )

                For i = 1 To 4

                   x = 4

                   For j = 1 To 3

                       x = 3

                       For k = 1 To 2

                          x = x + 6

                       Next k

                   Next j

                Next i

                Print x

            End Sub

程序运行后，单击命令按钮，输出结果是（　　　）

（A）7                    （B）15               （C）157                    （D）538

6．       在窗体上画一个命令按钮，然后编写如下事件过程：

            Private Sub Command_Click( )

                x = 0

                Do Until x = -1

                   a = InputBox(“请输入A的值：”)

                   a = Val(a)

                   b = InputBox(“请输入B的值：”)

                   b = Val(b)

                   x = InputBox(“请输入x的值：”)

                   x = Val(x)

                   a = a + b + x

                Loop

                Print a

            End Sub