在窗体上画一个名为Command1的命令按钮,其Command1_Click事件过程如下：

Sub Command1_Click()

Dim student As studtype

Dim record_no As Integer

record_no=1

With student

.ino=12

.strname="smith"

.strsex="男"

.smark=89

End With

_______

Put # 1,record_no,student

Close # 1

End Sub

要求在c: \的随机文件student.dat写入一条记录。应在程序中空行处填以下哪条语句使该功能完整

A．Open "c: \student.dat"For Input As #1 len(student)

B．Open "c: \student.dat"For random As #1 len(student)

C．Open "c: \student.dat"For Output As #1 len(student)

D．Open "c: \student.dat"For Append As #1 len(student)