在窗体上画一个名称为Command1的命令按钮，然后编写如下事件过程：
Private Sub Command1_Click( )
Dim m As Integer，i As Integer，x(3)As Integer
For i=0 To 3 : x(i)=i:Next i
For i=1 To 2:Call subl(x，i):Next i
For i=0 To 3:Print x(i)；:Next i
End Sub
Private Sub subl(a( )As Integer，k As Integer)
Dim j As Integer
Do
a(k)=a(k)+a(k+1)
j=j+1
Loop While j＜2
End Sub
程序运行后，单击命令按钮，则窗体上显示的内容是______。

A．89
B．99
C．23
D．77

A．Open "c:\Filel.txt＂　For　Ｉnput As　#１
Do While Not　EOF( )
Line　Input #1，strLine
Loop
B．Open "c: \File1.txt" For Input As #1
Do While Not EOF(#1)
Line Input #1, strLine
……
Loop
C．FileNo=Freefile
Open FileNo For Input As#1
Do While Not EOF(FileNo)
Line Input #1，strLine
Loop
D．FileNo=FreeFile
Open FileNo For Input As#1
Do While Not EOF(#FileNo)
Line Input#1，strLine
Loop