单项选择题

下列程序的执行结果为
Private Sub Command1_Click( )
Dim FirStr As String
FirSt=”abcdef，
Print Pat(FirStr)
End Sub
Private Function Pat(xStr As String)As String
Dim TempStr As String，strLen As Integer
tempStr=””
strLen=Len(xStr)
i=1
Do While i＜=Len(xStr)-3
tempStr=tempStr+Mid(xStr，i，1)+Mid(xStr，strLen-i+1，1)
i=i+1
Loop
Pat=tempStr
End Function