单项选择题

窗体中有文本框Text1。运行程序,输入大于0的整数m,单击按钮Command1,程序显示由星号组成的高度和上底均为m的等腰梯形形。例如,当m=5时,显示图形如下。 * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *事件代码如下。Private Sub Command1_Click() m = Val(Me!Text1) result = "" For k = 1 To m For n = 1 To 【 】 If n < m - k + 1 Then result = result & " " Else result = result & " *" End If Next n result = result + Chr(13) Next k MsgBox result, , "运行结果"End Sub程序【 】处应填写的语句是

A.k + 2 * m - 2
B.k + 2 * m
C.k + m - 1
D.k + m