单项选择题

运行下面的程序,单击命令按钮,输出结果为( )。
Function F(a As Integer)
b=0
Static c
b=b+1
c=c+1
F=a+b+c
End Function
Private Sub Command1_Click()
Dim a As Integer
a=2
For i=1 To 3
Print F(

A.
Next i
End SubA) 3
3
3
B.3
4
5
C.3
5
7
D.3
6
9