单项选择题

工程文件中包含一个模块文件和一个窗体文件。模块文件的程序代码是:
Public x As Integer
Private y As Integer
窗体文件的程序代码是:
Dim a As Integer
Private Sub Form_Load( )
Dim b As Integer
a =2: b =3: x =10: y =20
End Sub
Private Sub Command1_Click( )
a =a +5: b =b +5: x =x +5: y =y +5
Print a; b; x; y
End Sub
运行程序,单击窗体上的命令按钮,则在窗体上显示的是( )。

A) 5 5 15 5
B) 7 5 15 25
C) 7 8 15 5
D) 7 5 15 5